ICSE WITH SOUVIC: CHEMISTRY

chemistry model paper 1

Chemistry - Analytical Chemistry Use of NaOH and NH₄OH

Question .1. Using Sodium hydroxide solution, how would you distinguish :

(i) Zinc nitrate (or sulphate)solution and Calcium nitrate solution?

(ii) Iron (II) chloride from Iron (III) chloride?

(iii) Lead hydroxide from Magnesium hydroxide?

Question .2. (i) Sodium hydroxide solution is added to solution A. A white precipitate is formed which is insoluble in excess of Sodium hydroxide solution. What is the metal ion present in solution A?

(ii) When Ammonium hydroxide solution is added to solution B a pale blue precipitate is formed. This pale blue precipitate dissolves in excess of Ammonium hydroxide giving an inky blue solution. What is the cation present in solution B? What is the probable colour of solution B?

Question .3. You are given the three white powders Calcium carbonate, Lead carbonate and Zinc carbonate. Describe the tests you would carry out in solution to identify the metal in each of the above compounds. Indicate clearly how you would prepare the solutions for the tests.

Question .4. Write an equation for the following reaction :

Copper sulphate solution is added to Sodium hydroxide solution.

Question .5. Three test-tubes contain Calcium nitrate solution, Zinc nitrate solution and Lead nitrate solution respectively. Each solution is divided into two portions (i) and (ii). Describe the effect of :

(i) Adding Sodium hydroxide to each portion in turn till it is in excess.

(ii) Adding Ammonium hydroxide to each portion in turn till it is in excess.

Question .6. State what do you observe when : Ammonium hydroxide is added to Iron (III) sulphate solution.

Question .7. The following table shows the tests a student performed two aqueous solutions A and B. Write down the observations (i) and (ii) that were made.

Test	Observation	Conclusion
(i) To solution A, Sodium hydroxide solution was added.	(i)	A contains Fe³⁺ ions
(ii) To solution B, Ammonium hydroxide solution was added slowly till in excess.	(ii)	B contains Cu²⁺ ions

Question .8. How would you distinguish between Zn2+ and Pb2+ using ammonium hydroxide solution?

Question .9. Write observations and balanced equations for the following reactions.

(i) Sodium hydroxide is added drop wise till in excess to a solution of Zinc sulphate.

(ii) Ammonium hydroxide is added first in a small quantity and then in excess to a solution of copper sulphate.

(iii) Excess of Ammonium hydroxide is added to a substance obtained by adding hydrochloric acid in silver nitrate solution.

Question .10. Sodium hydroxide solution is added first in a small quantity, then in excess to the aqueous salt solution of copper (II) sulphate, zinc nitrate, lead nitrate, calcium chloride and iron (III) sulphate. Copy the following table and write the colour of the precipitate in (i) to (v) and the nature of the precipitate (soluble or insoluble) in (vi) to (x).

Aqueous salt solution.	Colour of precipitate when NaOH is added in a small quantity.	Nature of precipitate (soluble or insoluble) when NaOH is added in excess.
Copper (II) sulphate	(i)	(vi)
Zinc nitrate	(ii)	(vii)
Lead nitrate	(iii)	(viii)
Calcium chloride	(iv)	(ix)
Iron (II) sulphate	(v)	(x)

Question .11. The questions (i) to (v) refer to the following salt solutions listed A to F:

(A) Copper nitrate

(B) Iron (II) sulphate

(C) Iron (III) chloride

(D) Lead nitrate

(E) Magnesium sulphate

(F) Zinc chloride.

(i) Which two solutions will give a white precipitate when treated with dilute hydrochloric acid followed by barium chloride solution?

(ii) Which two solutions will give a white precipitate when treated with dilute nitric acid followed by silver nitrate solution?

(iii) Which solution will give a white precipitate when either dilute hydrochloric acid or dilute sulphuric acid is added to it?

(iv) Which solution becomes a deep/inky blue colour when excess of ammonium hydroxide is added to it?

(v) Which solution gives a white precipitate with excess ammonium hydroxide solution?

Question .12. From the list of substances given – Ammonium sulphate, Lead carbonate, chlorine, Copper nitrate, Ferrous sulphate – State a solution of the compound which gives a dirty green precipitate with sodium hydroxide.

Question .13. Write a balanced equation for the reaction between – aluminium oxide and sodium hydroxide solution.

Question .14. Give one test to distinguish between the following : - Iron (III) chloride solution and copper chloride solution.

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Solutions.

Q1. Solution:

(i)

Zinc nitrate (or sulphate)	Calcium nitrate
When Sodium hydroxide solution is added a white precipitate is formed which is soluble in excess of sodium hydroxide.	When Sodium hydroxide solution is added a white precipitate is formed which is insoluble in excess of Sodium hydroxide.

(ii)

Iron (II) chloride	Iron (III) chloride
When sodium hydroxide is added, dirty green precipitate is formed which changes to reddish brown after some time.	When sodium hydroxide solution is added, a reddish brown precipitate is formed.

(iii)

Lead hydroxide	Magnesium hydroxide
When sodium hydroxide is added, lead hydroxide is dissolved in it.	When sodium hydroxide is added, there is no visible reaction i.e. it remains insoluble.

Q2. Solution:

(i) Calcium ion [Ca²⁺]

(ii) Copper ion [Cu²⁺]. The colour of solution ‘B’ is blue.

Q3. Solution:

Calcium carbonate	Lead carbonate	Zinc carbonate
Calcium carbonate is dissolved in dilute Nitric acid and then Ammonium hydroxide is added to it. No visible reaction is seen.	Lead carbonate is dissolved in dilute Nitric acid and then Ammonium hydroxide is added to it. A white precipitate is formed which is insoluble in excess.	Zinc carbonate is dissolved in dilute Nitric acid and then Ammonium hydroxide is added to it. A white precipitate is formed which is soluble in excess.

Q4. Solution:

CuSO₄ + 2NaOH → Cu(OH)₂ + Na₂SO₄.

Q5. Solution:

(i) Sodium Hydroxide

	Small amount	In excess
Calcium nitrate	White precipitate	Insoluble
Zinc nitrate	White precipitate	Soluble
Lead nitrate	White precipitate	Soluble

Q6. Solution:

A reddish brown precipitate is formed.

Q7. Solution:

(i) Reddish brown coloured precipitate is appeared.

(ii) A pale blue or bluish white precipitate is formed which dissolves in excess of Ammonium hydroxide and give deep blue / intense blue / inky blue solution.

Q8. Solution:

Zn²⁺	Pb²⁺
On adding NH₄OH drop by drop to a solution of Zinc salt a white precipitate is formed which is soluble in excess of NH₄OH.	On adding NH₄OH drop by drop to a solution of lead salt a white precipitate is formed which is insoluble in excess of NH₄OH

Q9. Solution:

(i) When sodium hydroxide solution is added drop by drop to zinc sulphate solution a white precipitate is formed which is soluble in excess of sodium hydroxide.

ZnSO₄ + 2NaOH → Zn(OH)₂ + Na₂SO₄

Zn(OH)₂ + 2NaOH → Na₂ZnO₂ + 2H₂O.

(ii) When NH₄OH solution is added drop by drop to copper sulphate solution a pale blue / bluish white precipitate is formed which is soluble in excess of NH4OH and deep blue / inky blue solution is formed.

CuSO₄ + 2NH₄OH → Cu(OH)₂ + (NH₄)2SO₄

Cu(OH)₂ + 4NH₄OH → Cu(NH₃)₄(OH)₂ + 4H₂O.

(iii) When hydrochloric acid is added to silver nitrate solution a white precipitate is obtained which is soluble in excess of Ammonium hydroxide solution.

AgNO₃ + HCl → AgCl + HNO₃

AgCl + 2NH₄OH → [Ag(NH₃)₂]Cl + 2H₂O.

Q10. Solution:

Aqueous salt solution.	Colour of precipitate when NaOH is added in a small quantity.	Nature of precipitate (soluble or insoluble) when NaOH is added in excess.
Copper (II) sulphate	(i) Light Blue	(vi) Insoluble
Zinc nitrate	(ii) White	(vii) Soluble
Lead nitrate	(iii) White	(viii) Soluble
Calcium chloride	(iv) White	(ix) Insoluble
Iron (II) sulphate	(v) Dirty green	(x) Insoluble

Q11. Solution:

(i) B {iron (II) sulphate} and E [magnesium sulphate]

(ii) C [iron (III) chloride] and F [zinc chloride]

(iii) D [lead nitrate]

(iv) A [copper nitrate]

(v) D [lead nitrate].

Q12. Solution:

Ferrous sulphate.

Q13. Solution:

Al2O3 + 2NaOH → 2NaAlO₂ + H₂O.

Q14. Solution:

Iron (III) chloride solution	Copper chloride solution
When NaOH solution is added a dirty green precipitate of iron (III) hydroxide is formed.	When NaOH solution is added a bluish precipitate of copper (II) hydroxide is formed.

WORK SHEET ON ELECTROLYSIS BY SOUVIC JATI 9831497662

Q. 1. During the electrolysis of molten lead bromide, which of the following takes place :
A : Bromine is released at the cathode. B: Lead is deposited at the anode.
C : Bromine ions gain electrons. D: Lead is deposited at the cathode.

Q. 2. Here is an electrode reaction : Cu → Cu²⁺ + 2e^-. [i.e. Cu^- 2e^- →Cu²⁺]. At which electrode(anode or cathode) would such a reaction take place. Is this an example of oxidation or reduction.

Q. 3. A solution contains magnesium ions(Mg²⁺), iron (II) ions (Fe²⁺) and copper ions (Cu²⁺). On passing an electric current through this solution which ions will be the first to be discharged at the cathode. Write the equation for the cathode reaction.

Q.4. An electrode ‘A’ is connected to the positive terminal of a battery and electrode ‘B’ to the negative terminal.
(i) Give the names of the electrodes A & B.
(ii) Which electrode is the oxidizing electrode.

Ans : - Q. 5. State the appropriate term used for : – A liquid or solution, which conducts electricity with accompanying chemical change.

Ans.: - Q.6. Electrons are getting added to an element Y.
(i) Is Y getting oxidized or reduced?
(ii) What charge will Y have after the addition of electrons?
(iii) Which electrode will Y migrate to during electrolysis?

Ans : - Q. 7. Explain how electrolysis is an example of redox reaction.

Q. 8. What kind of particles will be found in a liquid compound which is a non-electrolyte?

Ans.: - Q.9. Complete the sentence by choosing the correct words – Electrolysis is the passage of ………… [electricity / electrons] through a liquid or a solution accompanied by a …………. [physical / chemical] change.

Q.10. Name a liquid which is a non-electrolyte.

Q.11. Name one substance which contains : (i) ions only (ii) molecules only (iii) both ions and molecules.

Q. 12. (i) What is meant by the term ‘electrolyte’.
(ii) What are the particles present in a compound which is non-electrolyte?
(iii) If an electrolyte is described as a ‘strong electrolyte’, what does this mean.

Q. 13. Explain why (i) solid sodium chloride does not allow electricity to pass through. (ii) copper, though a good conductor of electricity , is a non-electrolyte.

Q. 14. Classify the following substances under three headings: (i) Strong Electrolytes (ii) Weak Electrolytes (iii) Non Electrolytes – Acetic acid, ammonium chloride, ammonium hydroxide, carbon tetrachloride, dilute hydrochloric acid, sodium acetate, dilute sulphuric acid.

Q. 15. Fill in the blanks : -

(i) As we descend the electrochemical series containing cations, the tendency of the cations to get _________ [oxidized / reduced] at the cathode increases.
(ii) The [higher / lower] _________ the concentration of an ion in a solution, the greater is the probability of its being discharged at its appropriate electrode.

Q.16. (i) Name a solid which undergoes electrolysis when molten.
(ii) What should be the physical state of lead bromide if it is to conduct electricity?
(iii) What particles are present in pure lead bromide? Write the equations for the reactions which take place at the electrodes during the electrolysis of lead bromide.
(iv) Supply the word [or words] that will make the sentence into a correct statement which is to be written down again completely : - The electrolysis of lead bromide liberates lead and bromine.

Q. 17. If the compound formed between X [a metal with valency 2] and Y [a non-metal with valency 3] is melted and an electric current passed through the molten compound , the element X will be obtained at the ________ and Y at the _______ of the electrolytic cell. [Provide the missing words.]

Q.18.(i) Write the equations of the reactions which take place at the cathode and anode when acidified water is electrolyzed.
(ii) Name the gas released at the cathode when acidulated water is electrolyzed.
(iii) Copy and complete the following sentence: With platinum electrodes hydrogen is liberated at the ________ and oxygen at the _________ during the electrolysis of acidified water.
(iv) When the electrolysis of acidified water is carried out: [1] What is the ratio of the volume of hydrogen produced to the volume of oxygen. [2] Give the equation for the discharge of ions at the cathode.

Q.19. (i) If HX is a weak acid, what particles will be present in its dilute solution apart from those of water.
(ii) Write down the words or phrase from the brackets that will correctly fill in the blanks in the following:
(1) Pure water consists almost entirely of ______ (ions / molecules).
(2) We can expect that pure water ________ (will / will not) normally conduct electricity.
(iii) To carry out the so-called “electrolysis of water”, sulphuric acid is added to water. How does the addition of sulphuric acid produce a conducting solution.

Q. 20. (i) State what is observed when copper sulphate solution is electrolyzed using a platinum anode.
(ii) What ions must be present in a solution used for electroplating a particular metal.
(iii) A solution of silver nitrate is a good electrolyte but it is not used for electroplating an article with silver.
(iv) Choosing only words from the following list write down the appropriate word to fill in the blanks below : -
‘anions, anode, cathode, cations, electrode, electrolyte, nickel, voltameter’.
To electroplate an article with nickel requires an (a) ________ which must be a solution containing (b) ________ ions. The article to be plated is placed as the (c) ________ of the cell in which the plating is carried out. The (d) ________ of the cell is made from pure nickel. The ions which are attracted to the negative electrode and discharged are called (e) _______ .

Q. 21. (a) Select the correct compound from the list – Ammonia, Copper oxide, Copper sulphate, Hydrogen chloride, Hydrogen sulphide, Lead bromide – which matches with the description given below : (i) A solution of this compound is used as the electrolyte when copper is purified. (ii) When the compound is electrolyzed in the molten state, lead is obtained at the cathode.
(b) Write two applications of electrolysis in which the anode diminishes in mass.
(c) Complete the following table which refers to two practical applications of electrolysis : -

	Anode	Electrolyte	Cathode
Silver plating of spoon		Solution of potassium argentocyanide
Purification of copper

Q. 22. The following questions refer to the electrolysis of copper sulphate solution with copper electrodes :
(i) Compare the change in mass of the anode.
(ii) What is seen to happen to the colour of the copper sulphate solution if platinum electrodes are used? Explain this observation.
(iii) What is the practical application of the electrolysis of copper sulphate solution? Briefly describe one such application.

Q. 23. Choose A, B, C or D to match the descriptions (i) to (v) below. Some alphabets may be repeated.
A. non-electrolyte.
B. strong electrolyte.
C. weak electrolyte.
D. metallic conductor.
(i) Molten ionic compound.
(ii) Carbon tetrachloride.
(iii) An aluminium wire.
(iv) A solution containing solvent molecules, solute molecules and ions formed by the dissociation of solute molecules.
(v) A sugar solution with sugar molecules and water molecules.

Q. 24. (i) Here is an electrode reaction:
Cu → Cu²⁺ + 2e.
At which electrode (anode or cathode) would such a reaction take place? Is this an example of oxidation or reduction?
(ii) A solution contains magnesium ions (Mg²⁺) iron (II) ions (Fe²⁺) and copper ions (Cu²⁺). On passing an electric current through this solution which ions will be the first to be discharged at the cathode? Write the equation for the cathode reaction.
(iii) Why is carbon tetrachloride, which is a liquid, a non-electrolyte?

ELECTROLYSIS ANSWERS BY SOUVIC JATI

1. D

2. At anode. Oxidation.

3. Mg²⁺

4. (i) A – Anode, B – Cathode. (ii) A.

5. Electrolytes.

6. (i) Reduced (ii) Negative (iii) Anode

7. Ans.: - A redox reaction is one in which reduction and oxidation occurs simultaneously.
(i) Cathode (Reducing electrode) : – At cathode, the cations gain electrons to form neutral atoms. As electrons are gained, the ion is said to be reduced.
(ii) Anode (Oxidizing electrode) : – At anode, the anions lose electrons to form neutral atoms. As electrons are lost, the ion is said to be oxidized.

8. Molecules.

9. Ans.: - Electricity, Chemical.

10. Ans.: - Alcohol.

11. Ans.: - (i) NaOH (ii) Alcohol (iii) NaCO₃.

12. Ans : - (i) Chemical compounds which conduct electricity either in a fused or in aq. solution state and undergo chemical decomposition due to the flow of current through it are called electrolytes.
(ii) Molecules only.
(iii) (a) They are electrolytes which allow a large amount of electricity to flow through them and hence are good conductors of electricity.
(b) Are almost completely dissociated in fused or aqueous solution state.
(c) The solution contains almost only free mobile – ions.

13. Ans : - (i) In sodium chloride, Na⁺ and Cl^- ions are not free to carry the electric current.
(ii) Copper metal is solid and has no mobile ions whereas an electrolyte should dissociate into oppositely charged ions to conduct the electric current.

14. Ans : - (i) Strong Electrolytes – Ammonium chloride, dilute hydrochloric acid, dilute sulphuric acid.
(ii) Weak Electrolytes – Ammonium hydroxide, acetic acid.
(iii) non Electrolytes – Carbon tetrachloride.

15. Ans : - (i) reduced (ii) higher

16. Ans : - (i) Lead bromide. (ii) Molten state.
(iii) Lead ions and Bromide ions.
At cathode Pb²⁺ + 2e^- → Pb
At anode 2Br^--1 – 2e^- → 2[Br]
2[Br] → Br₂ ↑
(iv) The electrolysis of molten lead bromide liberates lead and bromine.

17. Ans : - Cathode, Anode.

18. Ans.: - (i) At cathode 2H⁺ + 2e^-- → 2H → H₂.
At anode 2OH- – 2e- → 2OH → H₂O + O
O + O → O₂.
(ii) Hydrogen.
(iii) Cathode, Anode.
(iv) [1] 2 : 1.
[2] H⁺ + e^- → [H]
2[H] → H₂.

19. Ans.: - (i) Non-ionized molecules : H⁺ and X^-.
(ii) Molecules, will not.
(iii) Sulphuric acid ionizes to form ions.

20. Ans : - (i) Blue colour of the solution disappears.
(ii) Metal ions of the metal with which electroplating is done.
(iii) Because electroplating is not uniform due to very fast reaction.
(iv) (a) Electrolyte (b) Nickel (c) Cathode (d) Anode (e) Cations.

21. Ans : - (a) (i) Copper sulphate (ii) Lead bromide.
(b) (i) Electroplating of an article (ii) Electro-refining of metals.
(c)

	Anode	Electrolyte	Cathode
Silver plating of spoon	Pure silver	Solution of potassium argentocyanide	Spoon
Purification of copper	Impure block of copper	Copper sulphate solution	Pure strip of copper

22. Ans : - (i) Anode diminishes in mass.
(ii) The colour of the solution fades since the blue Cu²⁺ ions which are discharged at the cathode are not replaced or added at the anode.
(iii) Electro-refining of impure copper. The pure copper metal dissolves out from the copper anode [impure copper block] and the Cu²⁺ ions formed in solution at the anode are deposited at the cathode [the thin pure sheet of copper]. The impurity present in impure copper anode settle down as anode mud or slime which contains insoluble gold and silver. Impurities such as iron, zinc etc ionize and dissolve in the electrolytic copper sulphate solution.

23. Ans : - (i) B (ii) A (iii) D (iv) C (v) A.

24. Ans : - (i) The reaction take place at anode. This is an example of oxidation.
(ii) Mg²⁺.
(iii) Carbon tetrachloride is a covalent compound and do not undergo chemical decomposition due to the flow of current through it.

Chemistry - Ammonia COMPILED BY SOUVIC JATI

Question.1. (i) Write an equation for solutions of ammonium chloride and sodium hydroxide are heated.

(ii) Ammonium salts decompose on heating. What other property do ammonium salts have in common?

(iii) Choose the correct word from the bracket and write a balanced equation for the same : Heating ammonium chloride with sodium hydroxide produces ______ [ammonia / nitrogen].

(iv) Name [formula is not acceptable] the gas produced on warming ammonium sulphate with sodium hydroxide solution.

(v) Write the equation for the preparation of NH₃ from ammonium chloride and calcium hydroxide.

(vi) Write the equation for the reaction when a mixture of ammonium chloride and slaked lime is heated.

(vii) From the list of substances given – Ammonium sulphate, Lead carbonate, Chlorine, Copper nitrate, Ferrous sulphate – State : A compound which on heating with sodium hydroxide produces a gas which forms dense white fumes with hydrogen chloride.

Q.2. (i) How is ammonia collected? Why is ammonia not collected over water ?

(ii) Which compound is normally used as a drying agent for ammonia ?

(iii) Name a substance used for drying ammonia.

Q.3. (i) The following reactions are carried out :

A : Nitrogen + Metal → Compound X.

B : X + Water → Ammonia + Another compound.

C : Ammonia + Metal oxide → Metal + Water + N₂.

(1) One metal that can be used for reaction A is magnesium.

(a) Write the formula of the compound X formed.

(b) Write the correctly balanced equation for reaction B where X is the compound formed.

(c) What property of ammonia is demonstrated by reaction C.

(ii) Write the equation for the formation of ammonia by the action of water on magnesium nitride.

(iii) Write the equation for the reaction of Aluminium nitride and water.

Q.4. (i) What is the purpose of Haber’s Process.

(ii) Name the gaseous inputs of the Haber’s process and state the ratio by volume in which the gases are mixed.

(iii) What is done to increase the rate of the reaction in the Haber’s Process.

(iv) Give two different ways by which the product can be separated from the reactant.

(v) Write the equation for the reaction in the Haber’s Process that forms ammonia.

(vi) State the purpose of liquefying the ammonia produced in the process.

(vii) With reference to Haber’s Process for the preparation of ammonia, write the equation and the conditions required.

Q.5. (i) How soluble is ammonia in water.

(ii) Give two reasons to show that the solution of ammonia in water contains hydroxide ions.

(iii) Is ammonia more dense or less dense than air.

Q.6. (i) Write equation for the following:

(a) Burning of ammonia in oxygen (b) Catlytic oxidation of ammonia. What do you observe in (a)? Name the catalyst used in (b). In the reaction referred to in (b), the catalyst glows red hot. Why? What is the name of the industrial process which starts with the reaction referred to in (b).

(ii) From the gases – ammonia, hydrogen chloride, hydrogen sulphide, Sulphur dioxide – Select the following: (a) When this gas is bubbled through copper sulphate solution, a deep blue coloured solution is formed. (b) This gas burns in oxygen with a green flame.

Q.7. (i) Name a simple method you would employ to prepare ammonium salts in your laboratory.

(ii) What property of ammonia is demonstrated by the Fountain Experiment. Write the balanced equation for the reaction between ammonia and sulphuric acid.

(iii) Choose the correct word from the brackets for each sentence and write a balanced equation for the same.

(a) Ammonium chloride is a soluble salt prepared by ______ (precipitation, neutralization).

(b) When ammonium chloride is heated, it undergoes thermal ______ (decomposition / dissociation).

(iv) Name a gas whose solution in water is alkaline.

(v) Name the ion other than ammonium ion formed when ammonia dissolves in water.

(vi) Select the correct compound from the list given – Ammonia, Copper oxide, Copper sulphate, Hydrogen chloride, Hydrogen sulphide, Lead bromide – which matches the description given below:

Although this compound is not a metal hydroxide, its aqueous solution is alkaline in nature.

.
Q.8. (i) How would you distinguish between Zn²⁺ans Pb²⁺ using ammonium hydroxide solution.

(ii) State what is observed when excess of ammonia is passed through an aq. solution of lead nitrate.

Q.9. (i) What are the products formed when ammonia is oxidized with copper oxide.

(ii) From the following gases – ammonia, chlorine, hydrogen chloride, Sulphur dioxide, select the gas that matches the description given below:

(a) The gas [B] turns moist red litmus paper blue. What is the name of gas [B]?

(b) Write the equation for the reaction that takes place when gas [B] is passed over heated CuO.

(iii) Write an equation for the reaction of chlorine with excess of ammonia.

(iv) Write a balanced chemical equation to illustrate the reducing nature of ammonia.

Q.10. (i) What do you observe when ammonia gas is bubbled through red litmus solution.

(ii) State what you observe when a piece of moist red litmus paper is placed in a gas jar of ammonia.

SOLUTION OF AMMONIA compiled BY SOUVIC JATI

Q1. Solution:

Δ
(i) NH₄Cl + NaOH → NaCl + H₂O + NH₃.

(ii) (a) Ammonium salts liberate ammonia on treatment with alkalies.

(b) All ammonium salts are soluble in water.

(iii) Ammonia.

NH₄Cl + NaOH → NaCl + H₂O + NH₃

(iv) Ammonia.

Δ
(v) 2NH4Cl + Ca(OH)₂ → CaCl₂ + 2H₂O + 2NH₃.

Δ
(vi) 2NH₄Cl + Ca(OH)₂ → CaCl₂ + 2H₂O + 2NH₃.

(vii) Ammonium sulphate.

Q2Solution:

(i) (a) Ammonia gas is lighter than air and hence collected by the downward displacement of air.[V.D. of NH₃ = 8.5, V.D. of air = 14.4]

(b) Ammonia is not collected over water since it is highly soluble in water.

[1 vol. of water dissolves about 702 vol. at 20 ºC and 1 atmos. pressure].

(ii) Quicklime [CaO]. (iii) Quicklime [CaO].

Q3Solution:

(i) (a) Magnesium nitride. [Mg₃N₂]

(b) Mg₃N₂ + 6H₂O → 3Mg(OH)₂ + 2NH₃ ↑.

(ii) Mg₃N₂ + 6H₂O → 3Mg(OH)₂ + 2NH₃ ↑.

(iii) AlN + 3H₂O → Al(OH)₃ + NH₃ ↑.

Q4. Solution:

(i) Manufacture of Ammonia.

(ii) Nitrogen [N₂] and Hydrogen [H₂] in the ratio 1:3 by volume.

(iii) Temperature is kept low and pressure high.

(iv) (a) Liquefaction – Ammonia is easily liquefied and hence separated from nitrogen and hydrogen. (b) Dissolving in water – Ammonia is highly soluble in water and hence separated from nitrogen and hydrogen.

(v) N₂ + 3H₂ → 2NH₃ + Δ.

(vi) Ammonia is easily liquefied while nitrogen and hydrogen are not easily separated. Hence ammonia is separated from nitrogen and hydrogen.

(vii) N₂ + 3H₂ → 2 NH₃ + Δ.

Ratio of nitrogen and hydrogen is taken as 1:3. Temperature is kept 450-500ºC and pressure at 200 to 900 atmos. Catalyst iron with promoter molybdenum is used

Q5. Solution:

(i) Ammonia is highly soluble in water. 1 vol. of water dissolves 702 vol. of ammonia at 20 ºC and 1 atm. pressure.

(ii) (a) Ammonia turns red litmus solution blue. (b) Ammonia reacts with acids to form salt and water.

(iii) Ammonia is less dense than air. [V.D. of ammonia = 8.5 while V.D. of air = 14.4].

Q6. Solution:

(i) (a) 4NH₃ + 3O₂ → 2N₂ + 6H₂O.

Pt
(b) 4NH₃ + 5O₂ → 4NO + 6H₂O + Δ .
800ºC

Observation – Dry ammonia does not burn when passed through ignited tube. When ammonia is passed through ignited tube with a passage of oxygen, ammonia burns with a greenish yellow flame forming nitrogen and water.

Catalyst – Catalyst used is Platinum. The catalyst glows since the catalytic oxidation of ammonia is an exothermic reaction.
The industrial process is known as ‘Ostwald’s Process’ for the manufacture of Nitric Acid.

(ii) (a) When ammonia gas is passed through Copper sulphate solution, pale blue precipitate of copper hydroxide is formed. On passage of excess ammonia the pale blue precipitate turns into deep blue coloured solution due to formation of tetra amine copper(II) sulphate.

CuSO₄ + 2NH₄OH → (NH₄)₂SO₄ + Cu(OH)₂ ↓

Cu(OH)₂ + (NH₄)₂SO₄ + 2NH₄OH → [Cu(NH₃)₄]SO₄ + 4H₂O.

(b) Ammonia.

ACID BASES AND SALT QUESTIONS COMPILED BY SOUVIC JATI

Q.1. State what would you see when Lead nitrate crystals are heated in a dry test-tube?

Q. 2. How will you convert the followings :
(i) CuSO₄ → CuCO₃ → CuO → CuSO₄
(ii) CuSO₄ → Cu(OH)₂ → CuO → CuSO₄.

Q.3. (i) Define an acid.
(ii) What is an alkali?
(iii) Explain the meaning of the term acid salt.

Q. 4. Answer the following questions relating to salts and their preparation :
        a) What is salt ?
        b) What kind of salt is prepared by precipitation ?
        c) Name a salt prepared by direct combination. Write the equation for the reaction that takes place when preparing the salt you have named.
        d) What procedure would be used to prepare Sodium salt such as Sodium sulphate. (Give the name of the procedure only).

Q.5. For each of the salts A, B, C and D, suggest a suitable method of preparation which relates to its description given below :
a) ‘A’ is Sodium salt.
b) ‘B’ is an insoluble salt.
c) ‘C’ is a soluble salt of Copper.
d) ‘D’ is a soluble salt of Zinc.

Q.6. (a) Define pH-scale.
(b) The pH value of pure water is 7. Compare the pH values of Sulphur dioxide solution and Ammonia solution with that of pure water.

Q.7. Sulphuric acid can be used to prepare a number of gases in the laboratory. Write balanced equation for reaction in which the following gases are obtained using dilute Sulphuric acid as one of the reactants.
(a) Hydrogen (b) Carbon dioxide (c) Sulphur dioxide.

Q.8. What is the meaning of the term Water of Crystallization?

Q.9. Name :
(i) two bases which are not alkalis.
(ii) a normal salt and acid salt of same acid.
(iii) a salt insoluble in cold water but soluble in hot water.

Q.10. From the following list of substances, choose those which meet the description given below :
Ammonium chloride, Ammonium nitrate, Chlorine, dilute Hydrochloric acid,
Iron, Lead nitrate, Magnesium (IV) oxide, Silver nitrate, Sodium nitrate,
Sulphur. Two compounds whose aqueous solution gives white precipitate with
dilute Hydrochloric acid.

Q.11. What do you see when Barium chloride solution is added to dilute Sulphuric acid?

Q.12. A solution has a pH of 7. Explain how you would :
(i) increase its pH. (ii) decrease its pH.

Q.13. If a solution changes the colour of litmus from red to blue, what can you say about its pH?

Q.14. What can you say about the pH of a solution that liberates Carbon dioxide form Sodium carbonate?

Q.15. Write equations for each of the following reactions:
(i) Chlorine is passed over heated iron.
(ii) Copper sulphate solution is added Sodium hydroxide solution.

Q.17. Name from the list of substances given below, the substances you would use to prepare each of the following salts named in part (a) to (d): Copper, Lead, Sodium, Zinc, Copper oxide, Lead carbonate, Sodium carbonate solution, dilute Hydrochloric acid, dilute Nitric acid and dilute Sulphuric acid. (a) Zinc sulphate (b) Copper sulphate (c) Sodium sulphate (d) Lead sulphate.

Q.18. (i) What is the purpose of pH-scale?
(ii) What is the pH of pure water?
(iii) ‘A’ is a soluble acidic oxide, ‘B’ is a soluble base. Compare the pH of pure
water, what will be the pH of :
(1) a solution of ‘A’, (2) a solution of ‘B’.

Q.19. Taking Sodium carbonate as an example, give the meaning of the following
terms: (i) Anhydrous (ii) Effloresence.

Q.20. Barium chloride solution can be used to distinguish between a Sodium sulphate solution and a Sodium nitrate solution. How is this done?

Q.21. Outline the steps required to convert Hydrogen chloride to anhydrous Iron (III) chloride. Write the equations for the reactions which take place.

Q. 22. (i) What are the two steps to change Lead carbonate to Lead chloride?
(ii) Give the name of a soluble salt of lead and write the equation for the action of heat on this salt.

Q.23. Answer the questions below, relating your answer only to the salt in the following list :
Sodium chloride, Anhydrous Calcium chloride, Copper sulphate-5-water.
(a) What name is given to the water in the compound Copper sulphate-5-water?
(b) If Copper sulphate-5-water is heated, the water is driven off, leaving Anhydrou Copper sulphate. What is the colour of Anhydrous Copper sulphate?
(c) What is deliquescence?
(d) Which one of the salts in the given list is deliquescent?

Q.24. State what you see when :
(a) Silver nitrate solution is added to dilute Hydrochloric acid.
(b) Zinc oxide is heated.

Q.25. Write correctly the balanced equations for the following reactions:
(a) Molten Sodium and Chlorine. (b) Iron and dilute Sulphuric acid.

Q.26. The compound Na₂B₄O₇.10H2Ois commonly known as Borax. When litmus is added to a solution of borax, it turns blue. What can you say about the pH of the Borax solution?

Q.27. What will you see when Barium chloride solution is added to Iron (II) Sulphate solution?.

Q.28. How will the action of dilute Hydrochloric acid on Sodium carbonate and Sodium sulphite enable you to distinguish between these two compounds?

Q.29. Write correctly the balanced equations for the reaction of dilute Sulphuric acid with each of the following: (a) Copper carbonate (b) Lead nitrate solution (c) Zinc hydroxide..

Q.30. Solution P has a pH of 13, solution Q has a pH of 6 and solution R has a pH of 2.
(i) Which solution will liberate Ammonia from Ammonium sulphate?
(ii) Which solution is a strong acid?
(iii) Which solution contains solute molecules as well as ions?

Q.31. What are the term defined in each case :
(i) A salt containing a metal ion surrounded by other ions or molecules.
(ii) A bse which is soluble in water.

ACID BASES AND SALT ANSWERS COMPILED BY SOUVIC JATI

Q1.

Ans : - When Lead nitrate is heated, it melts and a reddish brown coloured gas (NO₂) is
evolved. The residue left is reddish brown which turns to light yellow on cooling of lead oxide.
2Pb(NO₃)₂ → 2PbO + 4NO₂ + O₂

Q. 2. Ans : - (i) CuSO₄ + Na₂CO₃ → CuCO₃ + Na₂SO₄
               CuCO₃ + Δ → CuO + CO₂
               CuO + H₂SO₄ (dil) → CuSO₄ + H₂O
          (ii) CuSO₄+ 2NaOH → Cu(OH)₂ + Na₂SO₄
               Cu(OH)₂ + Δ → CuO + H₂O
            CuO + H₂SO₄ (dil) → CuSO₄ + H₂O.

Q.3.

Ans : - (i) Acid : - An acid is a compound which when dissolved in water yields hydronium ions [H3O⁺] as the only positively charged ions.
(ii) Alkali : - An alkali is a compound which when dissolved in water yields hydroxyl ions [OH^-] as the only negatively charged ions.
(iii) Acid salt : - The salt formed by partial replacement of the replaceable hydrogen ion of an acid molecule by a basic radical [metallic or ammonium ion].

Q. 4.Ans : - (a) Salt : - A salt is a compound formed by partial or complete replacement
                (i) of the replaceable [ionizable] hydrogen ion of an acid
                (ii) by a metallic ion or ammonium ion [basic radical].
          (b) Insoluble salts are prepared by precipitation.
          (c) Iron (III) chloride or Ferric chloride
               2Fe (heated) + 3Cl₂ (dry) → 2FeCl₃
          (d) By neutralizing sodium carbonate or sodium hydroxide with dilute sulphuric acid :
               Na₂CO₃ + H₂SO₄ → Na₂SO₄+ H₂O + CO₂
               2NaOH + H2SO₄ → Na₂SO₄ + 2H₂O

Q.5. Ans : - (a) By neutralization :
NaOH + HCl → NaCl + H₂O
(b) By precipitation :
Pb(NO₃)₂ + 2NaCl → PbCl₂ + 2NaNO₃
(c) CuCO₃ + H₂SO₄ → CuSO₄+ H₂O + CO₂
(d) Simple displacement :
Zn + H₂SO₄ → ZnSO₄ + H₂

Q.6. Ans : - (a) pH-scale is a scale used for determining the acidic or alkaline character of a solution.
(b) pH of Sulphur dioxide solution is less than 7.
pH of Ammonia solution is more than 7.

Q.7. Ans : - (a) Zn + H₂SO₄ (dil) → ZnSO₄ + H₂.
Note :- Any other active metal (except Na, K) can be used.
(b) Na₂CO₃ + H₂SO₄ (dil) → Na₂SO₄ + H₂O + CO₂.
Note :- Any other metallic Carbonate or Bicarbonate (except Calcium & Lead).
(c) Na₂SO₃ + H₂SO₄ (dil) → Na₂SO₄ + H₂O + SO₂.
Note :_ Any other Sulphite or Bisulphite can be used.

Q.8. Ans : - Water of Crystallization – The definite number of water molecules which enter into loose chemical combination when the salt crystallizes out from its saturated solution.
Na₂CO₃.10H₂O is Sodium carbonate with ten water molecules of crystallization.

Q.9 Ans.: - (i) Magnesium hydroxide, Copper hydroxide.
(ii) Sodium sulphate and Sodium bisulphate.
(iii) Lead chloride.

Q.10. Ans : - Silver nitrate solution and Lead nitrate solution.
AgNO₃ + HCl → AgCl + HNO₃
Pb(NO₃)₂ + 2HCl → PbCl₂ + 2HNO₃

Q.11. Ans : - A white precipitate of Barium Sulphate is formed.
BaCl₂ + H₂SO₄ → BaSO₄ + 2HCl

Q.12. Ans.: - (i) By adding alkali (ii) By adding an acid.

Q.13. Ans.: - Its pH is more than 7.

Q.14.Ans.: - Its pH is less than 7.

Q.15 Ans.: - (i) 2Fe (heated) + 3Cl₂ (dry) → 2FeCl₃.
(ii) CuSO₄ + 2NaOH → Cu(OH)₂ + Na₂SO₄.

Q.17. Ans.: - (a) Zn + H₂SO₄ (dil) → ZnSO₄ + H₂
(b) CuO + H₂SO₄ (dil) → CuSO₄ + H₂O
(c) Na₂CO₃ + H₂SO₂ (dil) → Na₂SO₄ + H₂O + CO₂
(d) PbCO₃ + 2HNO₃ (dil) → Pb(NO₃)₂ + H₂O + CO₂
Pb(NO₃)₂ + H₂SO₄ (dil) → PbSO₄ + 2HNO₃.

Q.18. Ans.: - (i) pH scale is used to determine the acidic nature and alkalinity of a solution.
(ii) Seven.
(iii) (1) Less than 7, (2) More than 7.

Q.19. Ans : - (i) Anhydrous : Hydrated salt when heated lose their water of crystallization and are rendered anhydrous.
Na₂CO₂.10H₂O + Δ → Na₂CO₃ (anhydrous) + 10 H₂O.

(ii) Efflorescence : Hydrated salt when left exposed to atmosphere lose their water of crystallization and crumble down to form a powder. Such salts are known as efflorescent salt and the property is known as efflorescence. Na₂CO₃.10H₂O, on being exposed to atmosphere, loses its water of crystallization and crumbles to form powder.

Q.20. Ans : - When Sodium sulphate solution is treated with Barium chloride solution a white precipitate of Barium sulphate is formed which is insoluble in all the mineral acids. When Sodium nitrate solution is treated with Barium chloride solution, no
visible reaction is observed.
BaCl₂ + Na₂SO₄ → BaSO₄ ↓ + 2NaCl
BaCl₂ + 2NaNO₃ → Ba(NO₃)₂ + 2NaCl

Q.21. Ans.: - MnO₂ + 4HCl (conc) → MnCl₂ + Cl₂ + 2H₂O.
Chlorine thus obtained is dried by passing through concentrated Sulphuric acid. This dried chlorine is passed over heated Iron to get anhydrous Iron (III) chloride.
2Fe (heated) + 3Cl₂ (dry) → 2FeCl₃.

Q. 22. Ans.: - (i) PbCO₃ + 2HNO₃ (dil) → Pb(NO₃)₂ + H₂O + CO₂
Pb(NO₃)₂ + 2HCl (dil) → PbCl₂ + 2HNO₂.
(ii) Lead nitrate.
Pb(NO₃)₂ + Δ → 2PbO + 4NO₂ + O₂.

Q.23.Ans : - (a) Water of crystallization.
(b) White.
(c) Some salts, when exposed to atmosphere, absorbs moisture and is converted into their saturated solution. Such salts are called as deliquescent salts and the property as deliquescence.
(d) Anhydrous Calcium chloride.

Q.24. Ans.: - (a) When Silver nitrate solution is added to dilute Hydrochloric acid, white precipitate of Silver chloride is formed which is soluble in excess of Ammonium hydroxide.
(b) White coloured Zinc oxide changes to yellow.

Q.25.Ans.: - (a) 2Na + Cl₂ → 2NaCl.
(b) Fe + H₂SO₄ (dil) → FeSO₄ + H₂.

Q.26. Ans.: - More than 7.

Q.27. Ans.: - A white precipitate insoluble in all mineral acids is formed.

Q.28.Ans : - When Sodium carbonate react with dilute Hydrochloric acid a colourless and odourless gas with brisk effervescence is evolved which turns lime water milky.
Na₂CO₃ + 2 HCl (dil) → 2NaCl + H₂O + CO₂↑
Ca(OH)₂+ CO₂ → CaCO₂ + H₂O.
When Sodium sulphite reacts with dilute Hydrochloric acid, a gas with smell of burning Sulphur is evolved which turns orange colour of acidified Potassium dichromate to green and decolourises purple colour of Potassium permanganate solution.
Na₂SO₃ + 2HCl (dil) → 2NaCl + H₂O + SO₂
K₂Cr₂O₇ + 3SO₃+ H₂SO₄ → K₂SO₄ + Cr₂(SO₄)₃ + H₂O
2KMnO₄+ 2H₂O + 5SO₂ → K₂SO₄ + 2MnSO₄ + 2H₂SO₄.

Q.29. Ans : - (a) CuCO₃ + H₂SO₄(dil) → CuSO₄ + H₂O + CO₂
(b) Pb(NO₃)₂+ H₂SO₄ (dil) → PbSO₄ + 2HNO₃
(c) Zn(OH)₂ + H₂SO₄ (dil) → ZnSO₄ + 2H₂O.

Q.30. Ans.: - (i) P (ii) R (iii) Q.

Q.31.Ans : - (i) Complex salt.
(ii) Alkali.

Chemistry - Organic Chemistry (Solved) By SOUVIC JATI

Question .1. (i) Define the term ‘catenation’.
(ii) Which one of the elements – Li, Be, B, C, O, F, Ne shows the property of catenation

Question .2. (i) State the term for:- Compounds having the same general formula and similar chemical properties.
(ii) Name (a) The compound with – OH and with – COOH as the part of its structure.
(b) Homologue of homologus series with general formula CnH2n from the compounds given: Ethane, Ethene, Ethanoic acid, Ethyne, Ethanol.
Question .3. (i) State the structural formula of ethane.
(ii) Draw the structural formula of the two isomers of Butane. Give the correct IUPAC name of each.
(iii) From the following list, write down the appropriate words to fill in the blanks (a) to (e) below: - Addition, carbohydrates, CnH2n-2, CnH2n, CnH2n+2, electrochemical, homologus, hydrocarbons, saturated, substitution, unsaturated.
The alkane from an (a) ________ series with the general formula (b) __________. The alkanes are (c) __________ (d) __________ which generally undergo (e) ___________ reaction.
Question .4. (i) For each of the compounds (a) Ethane, (b) Vinegar [acetic acid] and (iii) Marsh gas [methane], draw the relevant structural formula. What word is used to describe the above three compounds taken together?
(ii) Draw the structural formula of ethane. What is the feature of the ethane structure which allows ethane to react with chlorine in the way it does.
(iii) Give the correct IUPAC name and the functional group for each of the compounds whose structural formulae are given below:
(a)

(b) Question .5. (i) What is the special feature of the structure of : (a) C2H4 (b) C2H2.
(ii) What type of reaction is common to both these compounds?
(iii) Give the name and structural formula of (a) a saturated hydrocarbon, (b) an unsaturated hydrocarbon with a double bond.
(iv) Copy and complete the following sentence: A saturated hydrocarbon will undergo _________ reactions whereas the typical reaction of an unsaturated hydrocarbon is _________.
(v) State the term defined by the following :- Compounds containing carbon and hydrogen only.
(vi) State the general formula for a saturated hydrocarbon and give one example and structural formula of the same.
(vii) Draw the structural formula of ethyne. How does the structure of alkynes differ from that of alkenes.
(viii) Fill in the blanks with the correct words : – Alkanes are the (a) _______ [analogous / homologous] series of (b) _______ [saturated / unsaturated] hydrocarbons. They differ from alkanes due to the presence of (c) _________ [double / single] bonds. Alkenes mainly undergo (d) ________ [addition / substiution] reactions.
Question .6. (i) Which compound is heated with soda lime to obtain C2H6 in the laboratory . Write the equation for the same.
(ii) Write the equation for the preparation of CH4 from anhydrous sodium ethanoate [sodium acetate]. Question .7. (i) What type of reaction has taken place between ethane and chlorine.
(ii) Write the equation of the complete combustion of ethane.
(iii) What is the type of reaction taking place between ethane and chlorine to form mono-chloro-ethane.
(iv) Write the equation for the preparation of carbon tetrachloride from methane.
(v) Write a balanced equation for the reaction of ethane and oxygen in presence of molybdenum oxide.
Question .8. (i) Name a solid used instead of conc. H2SO4to prepare ethylene by the dehydration of ethanol.
(ii) Write the equation for the preparation of ethylene from ethyl alcohol. Or, Write the equation for the reaction of heating ethanol at 170ºC in the presence of conc. H2SO4.
Question .9. (i) Write a balanced equation for the reaction between ethene and hydrogen.
(ii) State what do you observe when ethene is bubbled through a solution of bromine in tetrachloromethane (carbon tetrachloride).
(iii) The reaction between ethene and chlorine forms only one product. Name the type of this equation.
(iv) Ethylene forms an addition product with Cl2. Name the product and give its structural formula.
Question .10. (i) Write down the equation for the preparation of ethyne from calcium carbide.
(ii) Burning of acetylene (ethyne) in oxygen produces a very hot flame. What is this hot flame used for.
(iii) State one use of acetylene.
Question .11. (i) What is the type of reaction between ethene and chlorine.
(ii) What feature of the ethene structure makes such a reaction possible.
(iii) Name the product of the reaction between ethene and chlorine.
(iv) What is the special feature of the structure of ethyne.
(v) Ethanol can be converted to ethene which can then be changed to ethane. Choose the correct word or phrase from the brackets to complete the following sentences : -
(a) The conversion of ethanol to ethene is an example of ______ (dehydration / dehydrogenation).
(b) Converting ethanol to ethene requires the use of ________ (concentrated hydrochloric acid / concentrated nitric acid / concentrated sulphuric acid).
(c) The conversion of ethene to ethane is an example of _______ (hydration / hydrogenation).
(d) The catalyst used in the conversion of ethene to ethane is commonly ________ (iron / nickel / cobalt).
(vi) From the list given : - ethanol, ethane, methanol, methane, ethyne and ethene. Name a compound : -
(a) Formed by the dehydration of ethanol by concentrated sulphuric acid.
(b) Which will give a red precipitate with ammoniacal cuprous chloride solution.
(c) Which forms methanoic acid on oxidation in the presence of copper at 200ºC.
(d) Which has vapour density 14 and turns alkaline KMnO4 green.
4
(e) Which forms chloroform on halogenation in the presence of sunlight.
(f) Which decolourises bromine solution in carbon tetrachloride.

(vii) Write balanced equations for the preparation of the following : -
(a) Ethane from sodium propionate (b) Ethene from ethanol. (c) Ethyne from calcium carbide. (d) Ethanoic acid from ethane.
(viii) Name a reagent which can be used to distinguish between Ethane and ethene.
(ix) Write the equation for the preparation of ethylene from ethyl alcohol.
(x) Name a compound which will give acetylene gas when treated with water.
(xi) Write the equations for the following laboratory preparations : -
(a) Ethane from sodium propionate. (b) Ethene from Iodoethane. (c) Ethyne from calcium carbide. (d) Methanol from Iodomethane.
(xii) Draw the structural formula of a compound with two carbon atoms in each of the following cases : - (a) An alkane with a carbon to carbon single bond.
(b) An alcohol containing two carbon atoms.
(c) An unsaturated hydrocarbon with a carbon to carbon triple bond.

Solutions of organic chemistry icse compiled BY SOUVIC JATI

Q1. Solution:

(i) Catenation is defined as the tendency of an element to form chains of identical atoms.

(ii) C.

Q2. Solution:

(i) Homologus series.

(ii) (a) Ethanol and Ethanoic acid.

(b) Ethene [a member of Alkene]

Q3(iii) (a) Homologus

(b) CnH_2n+2

(d) Hydrocarbon

(e) Substitution.

Solution:

Q4. Solution:

(i) (a) Ethane is C2H6 and its structure formula is

(b) Vinegar is CH₃COOH (Acetic acid) and its structure formula is

These three compounds are called organic compound.

(ii)

Unsaturated Hydrocarbon with double bond.
(iii) (a) IUPAC name → Propanal, Functional group → – CHO.
(b) IUPAC name → Propanol, Functional group → – OH.

Q5Solution:

(i) Both are unsaturated hydrocarbons. C₂H₄ (Ethene) contain carbon to carbon double bond and C₂H₂ (Ethyne) contain carbon to carbon triple bond.

(ii) Both type of compounds undergo addition reactions.

(iii) (a) Saturated hydrocarbon : Ethane.

Structure formula of ethane.

(b)Unsaturated hydrocarbon with double bond : Ethylene (Ethene).

Structural formula of ethene.

(iv) substitution, addition reaction.

(v) Hydrocarbons.

(vi) General formula : CnH_2n+2.

Example : C₂H₆.

(vii) Structural formula of ethyne :

H – C ≡ C – H
Alkyne possess a triple bond between carbon to carbon atoms whereas alkenes possess a double bond between carbon to carbon atoms.

(viii) (a) Homologous (b) Unsaturated (c) Double (d) Addition.

Q6. Solution:

(i) Sodium propanoate [sodium propionate]

                                                      CaO
CH₃ – CH₂ – COONa + NaOH   →   C₂H₆ + Na₂CO₃
                                                     Δ   Ethane

(ii)                                      CaO
CH₃ – COONa + NaOH →    CH₄    + Na₂CO₃
                                       Δ   Methane

Q7. Solution:

(i) Substitution reaction.

Cl₂ Cl₂ Cl₂Cl₂ Cl₂
C₂H₆ + Cl₂ → C₂H₅Cl → C₂H₄Cl₂ → C₂H₃Cl₃ → C₂H₂Cl₄ → C₂HCl₅ → C₂Cl₆.

(ii) 2C₂H₆ + 7O₂ → 4CO₂ + 6H₂O + Heat.

(iii) Substitution reaction.

(iv) uv[light]
CH₄ + Cl₂ → CH₃Cl + HCl
or Δ

MoO
(v) C₂H₆ + O₂ → CH₃CHO + H₂O

[350-500ºC]

Q8Solution:

(i) Alumina at 350ºC.

Conc. H₂SO₄

(ii) C₂H₅OH → C₂H₄ + H₂O

160º – 170ºC

Q9. Solution:

(ii) Colour of bromine disappears.

(iii) Addition reaction.

(iv)

Q10Solution:

(i) CaC₂ + 2H₂O → Ca(OH)₂ + C₂H₂.

(ii) It is used for welding and cutting metals.

(iii) Welding and cutting metals.

Q11. Solution:

(i) Addition reaction.

(ii) Presence of double covalent bond.

(iii) 1,2-dichloro ethane.

(iv) Presence of triple covalent bond.

(v) (a) Dehydration (b) Concentrated sulphuric acid (c) Hydrogenation (d) Nickel

(vi) (a) Ethene or Ethylene (b) Ethyne or Acetylene (c) Methane of Methanol (d) Ethene or Ethylene (e) Methane (f) Ethene or Ethylene; Ethyne or Acetylene.

(vii) (a) CaO
C₂H₅COONa + NaOH → C₂H₆ + Na₂CO₃.

(b) Conc. H₂SO₄
C₂H₅OH → C₂H₄ + H₂O.

(d) 2C₂H₆ + 3O₂ → 2CH₃COOH + 2H₂O.

(viii) Bromine solution in carbon tetrachloride.

(ix) Conc. H₂SO₄

C₂H₅OH → C₂H₄ + H₂O.

(x) Calcium Carbide.

CaO
(xi) (a) CH₃CH₂COONa + NaOH → C₂H₆ + Na₂CO₃.

(b) CH₃CH₂I + KOH → C₂H₄ + KI + H₂O.

(d) CH₃I + KOH → CH₃OH + KI.

(x) (a)

(b)

CHEMICAL BONDING

QUESTION SHEET

Q.1. Elements X, Y, Z have atomic numbers 6, 9 and 12 respectively. Which one :

forms anion – negative ion;
forms cation – positive ion;
has 4 electrons in the outermost orbit.

Q. 2. Name a covalent compound which becomes electrovalent when dissolved in
water.

Q. 3. Elements A, B and C have atomic number 9, 20 and 10 respectively.

State which one is
(1) a non-metal;
(2) a metal;
(3) chemically inert.
Write down the formula of the compound formed by two of the above
elements.

Q. 4. Draw electron dot diagram to depict the formation of :
(i) Magnesium oxide from ²⁴Mg₁₂and ¹⁶O₈.
(ii) a molecule of chlorine from two atoms of ³⁵Cl₁₇.

Q. 5. (a) Write down the electronic configuration of the following:
(i) ²⁷X₁₃
(ii) ³⁵Y₁₇.

(b) Write down the number of electrons in X & neutrons in Y & the formula of the compound formed by X & Y.

Q.6. Covalent compounds are usually liquids or gases. Explain.

Q.7. Draw electron diagrams for the formation of : (i) sodium chloride (ii) hydrogen
sulphide [²³₁₁Na; ³⁵₁₇Cl; ¹₁H; ³²₁₆S].

Q. 8. Show the formation of carbon tetrachloride molecule using an electron “dot
and cross” diagram.

Q. 9. State two differences normally found between the properties of ionic and covalent compounds.

Q. 10. State two differences between the properties of carbon tetrachloride and sodium chloride.

Q. 11. Element X is a metal with a valency 2. Element Y is a non-metal with a valency 3.
(i) Write equations to show how X and Y form ions.
(ii) If Y is a diatomic gas, write the equation for the direct combination of X and Y to form a compound.
(iii) If the compound formed between X and Y is melted and an electric current passed through the molten compound, the element X will be obtained at the………… and Y at the ……….. of the electrolytic cell. (Provide the missing words).

Q.12. Compound X consists of molecules. Choose the letter corresponding to the correct answer from the choices A, B, C and D given below :
          (i) The type of bonding in X will be :
               (a) Ionic (b) Electrovalent (c) Covalent (d) Molecular.
          (ii) X is likely to have a :
               (a) low melting point and high boiling point
             (b) High melting point and low boiling point
               (c) low melting point and low boiling point
               (d) high melting point and high boiling point.
          (iii) In the liquid state, X will
               (a) become ionic
               (b) be an electrolyte
               (c) conduct electricity
               (d) not conduct electricity.

Q.13. Electrons are getting added to an element Y.
         (i) Is Y getting oxidized or reduced?
         (ii) What charge will Y have after the addition of electros?
        (iii) Which electrode will Y migrate to during the process of electrolysis?

Q.14.

Acids dissolve in water and produce positively charged ion. Draw the structur of these positive ions.
Explain why carbon tetrachloride does not dissolve in water?
Elements Q and S react together to form an ionic compound. Under normal conditions which physical state will the compound QS exist in?
Can Q and S both be metals?

Q. 15. (i) What is lone pair of electrons?
(ii) Draw an electron dot diagram of a hydronium ion and label the lone pair of electrons.
(iii) Name a neutral covalent molecule which contains one lone pair electrons.

Q.16. (i) Name the charged particles which attract one another to form electrovalent
compounds.
(ii) In the formation of electrovalent compounds, electrons are transferred from one element to another. How are electrons involved in the formation of a covalent compound?
(iii) The electronic configuration of nitrogen is 2, 5. How many electrons in the outer shell of a nitrogen atom are not involved in the formation of nitrogen molecule?
(iv) In the formation of magnesium chloride (by direct combination between magnesium and chlorine), name the substance that is reduced.

Q. 17. Which of the following is not a common characteristic of an electrovalent compound.
A : High melting point B : Conducts electricity when molten
C : Consists of oppositely charged ions. D : Ionizes when dissolved in water.

Q.18. Why is carbon tetrachloride which is a liquid – a non-electrolyte.

Q.19. What are the terms defined in each case :
(i) A bond formed by a shared pair of electrons, each bonding atom contributing one electron to the pair.
(ii) A bond formed by a shared pair of electrons with both electrons coming from the same atom.

CHEMICAL BONDING ANSWERS.

BY SOUVIC SIR 9831497662

souvicjati@gmail.com

1. Ans : -

2. Ans : - HCl or NH3.

3. Ans : - (i) (1) A (2) B (3) C (ii) BA₂.

4. Ans.: -
                         ..
   (i) Mg : + : O : → MgO
        . .       . .           . . . .
(ii)   :Cl . + . Cl : → : Cl : Cl :
        . .       . .          . .    . .

5. Ans.: -
(a)
(i) Electronic configuration of X = 2, 8, 3.
(ii) Electronic configuration of Y = 2, 8, 7.

(b) Number of electrons in X = 13; Number of neutrons in Y = 35 – 17 = 18;
Formula of the compound is XY₃.

6. Ans : - In covalent compounds, molecules have weak force of attraction between them and hence exist in liquids or gases state.

7. Ans :-
                      . .              . .
     (i)  Na . + . Cl : → Na : Cl :
                       . .             . .
                   . .
      (ii)  H * . S . * H
                  . .

8. Ans : -

                . .
              : Cl :
                . .

              . . * . .
     : Cl . *C* . Cl :
             . . *. . .
           : Cl :
             . .

9. Ans : -

Electrovalent (ionic) compound	Covalent compound
1. Exists as hard solid state. e.g. NaCl	1. Exists as soft solid, liquid or gases state. e.g. CCl₄
2. It is non-volatile. NaCl	2. It is volatile. CCl₄
3. High melting & boiling point. NaCl	3. Low melting & boiling point. CCl₄
4. Good conductors of heat. NaCl	4. Bad or non-conductors of heat. CCl₄
5. Non-conductors of electricity in solid state but good conductors in molten or aq. solution state. NaCl	5. Non-conductors of electricity. CCl₄
6. Can be electrolysed in molten or aq. solution state. NaCl	6. Cannot be electrolysed in normal state. Polar covalent compounds undergo electrolysis in solution state. CCl₄
.Soluble in water but insoluble in organic solvents. NaCl	7. Soluble in organic solvent (non-polar) but insoluble in water (polar). CCl₄
8. Undergo high speed ionic reactions. NaCl	8. Undergo slow speed molecular reactions. CCl₄
9. Undergo electrolytic dissociation on passage of electric current. NaCl	9. Undergo ionization in solution state on passage of electric current. CCl₄

10 Ans : - Consult answer of question 8.

11. Ans : -

(i) X → X²⁺+ + 2^e-
Y + 3^e-- → Y^3-
(ii) 3X + Y₂→ X₃Y₂(iii) Cathode, Anode.

12. Ans : - (i) (C) (ii) (C) (iii) (D)

13. Ans : - (i) reduced (ii) negative (iii) anode.

14. Ans : -              (i)         . . +
                            ! H – O – H !
                            !       ↓        !
                            !       H       !
(ii) Carbon tetrachloride is a non-polar covalent compound and does not dissolve in polar solvents      like water.
(iii) Solid
(iv) No, because for the formation of ionic compound, one element should be metal and the other       non-metal.

16. Ans : - (i) Cation and anion (ii) There is a mutual sharing of electrons
(iii) Two (iv) Magnesium is oxidized and chlorine is reduced.

17. Ans : - C.

18. Ans : - As CCl₄

has not free ions and hence are non-conductors. Hence it a non-electrolyte.

19. Ans : - (i) Covalent bond,
(ii) Covalent bond.

Periodic Properties and Variation in Properties

By souvic sir

souvicjati@gmail.com

Q. 1. State the number of elements in Period 1, Period 2 and Period 3 of the Periodic Table.

Q. 2. Name the elements in Period 1.

Q. 3. What happens to atomic size of elements on moving from left to right in a period?

Q. 4. What is the common feature of the electronic configuration of the elements at the end of Period 2 and Period 3?.

Q. 5. If an element is in group 7 (or group 7A), is it likely to be metallic or non- metallic in character?

Q. 6. Supply the missing word from those in brackets:
If an element has one electron in its outermost energy level, then it is likely to be ________ (metallic/non-metallic).

Q. 7. Complete the following sentences using the correct word.
(i) The properties of the elements are a periodic function of their ___________ (atomic number, mass number, relative atomic mass).
(ii) Moving across a ___________ of the Periodic Table, the elements show increasing ___________ character (group, period, metallic, non-metallic).
(iii) The elements at the bottom of a group would be expected to show __________ metallic character than the element at the top (less, more).
(iv) The similarities in the properties of a group of elements is because they have the same __________ (atomic number, electronic configuration, number outer electrons)..

Q. 8. What is meant by a Group in the Periodic Table?

Q. 9. Within a group where would you expect to find the element with:
(a) the greatest metallic character? (b) the largest atomic size?

Q.10. State whether the ionization potential increases or decreases on going down a Group.

Q.11. How many elements are there in Period 2?

Q.12. The following table represent The first three periods of the modern periodic table. Study the table and answer the questions that follow:

IA	2A	1B	2B	3B	4B	5B	6B	7B	8	8	8	3A	4A	5A	6A	7A	0
l																	2
H																	He
3	4											5	6	7	8	9	10
LI	Be											B	C	N	O	F	Ne
II	12											13	14	15	16	17	18
Na	Mg											Al	SI	P	S	Cl	Ar
19	20	21	22	23	24	25	26	27	28	29	30	31	32	33	34	35	36

(i) Write the formula of the sulphate of the element with atomic number 13.
(ii) What type of bonding will be present in the oxide of the element with atomic number 1?
(iii) Which features of the atomic structure accounts for the similarities in the chemical properties of the elements in group 7A of the periodic table?
(iv) Name the elements which has the highest ionization potential.
(v) How many electrons are present in the valency shell of the element with the atomic number 18?
(vi) What is the name given to the energy released when an atom in its isolated gaseous state accepts an electron to form an anion?
(vii) What is the electronic configuration of the element in the third period which gains one electron to change into an anion?
(viii) Fill in the blanks :
The atomic size ________ as we move from left to right across the period, because the __________ increases but the __________ remains the same.

Q. 13. The electro-negativities (according to Pauling) of the elements in period 3 of the Periodic Table are as follows with the elements arranged in alphabetical order:

Al	Cl	Mg	Na	P	S	Si
1.5	3.0	1.2	0.9	2.1	2.5	1.8

(i) Arrange the elements in the order in which they occur in the Periodic Table from left to right. (The group 1 element first, followed by the group 2 element and so on, up to group 7.)
(ii) Choose the word or phrase from the brackets which correctly completes each of the following statements:
(a) The element below sodium in the same group would be expected to have a ______ (lower/higher) electro-negativity than sodium and the element above chlorine would be expected to have a _________ (lower/higher) ionization potential than chlorine.
(b) On moving from left to right in a given period, the number of shells (remains the same/increases/decreases).
(c) On moving down a group, the number of valence electrons (remains the same/increases/decreases).

Q. 14. Parts (i) to (v) refer to changes in the properties of elements on moving left to right across a period of the Periodic Table. For each property, choose the letter corresponding to the correct answer from the choices a, b, c and d.
(i) The non-metallic character of the elements:
(a) decreases (b) increases (c) remains the same (d) depends on the period.
(ii) The electro-negativity:
(a) depends on the number of valence electrons (b) decreases
(c) remains the same (d) increases.
(iii) The ionization potential:
(a) goes up and down (b) decreases (c) increases (d) remains the same.
(iv) The atomic size:
(a) decreases (b) increases
(c) remains the same (d) sometimes increases and sometimes decreases.
(v) The electron affinity of the elements in group 1 to 7:
(a) goes up and then down (b) decreases and then increases
(c) increases (d) decreases.

Q. 15. The elements of one short period of the Periodic Table are given below in order from left to right.
Li Be B C O F Ne
(i) To which period do these elements belong?
(ii) One element of this period is missing. Which is the missing element and where should it be placed?
(iii) Which one of the elements in this period shows the property of catenation?
(iv) Place the three elements fluorine, beryllium and nitrogen in the order of increasing electro-negativity.
(v) Which one of the above elements belongs to the halogen series?

Q. 16. A group of elements in the Periodic Table are given below (Boron is the first member of the group and Thallium is the last):
Boron, Aluminium, Gallium, Indium, Thallium.
Answer the following questions in relation to the above group of elements :-
(i) Which element has the most metallic character?
(ii) Which element would be expected to have the highest electro-negativity?
(iii) If the electronic configuration of Aluminium is 2, 8, 3 how many electrons are there in the outer shell of Thallium?
(iv) The atomic number of boron is 5. Write the chemical formula of the compound formed when Boron reacts with Chlorine.
(v) Will the elements in the group to the right of this Boron group be more metallic or less metallic in character? Justify your answer.

Q. 17. With reference to the variation of properties in the Periodic Table, which of the following is generally true.
A Atomic size increases from left to right across a period.
B Ionization potential increases from left to right across a period.
C Electron affinity increases going down a group.
D. Electronegativity increases going down a group.

Q. 18. (i) Name the first and last element in period 2.
(ii) What happens to the atomic size of elements on moving from top to bottom of a group.
(iii) Which of the elements has the greatest electron affinity among the halogens.
(iv) What is the common feature of the electronic configurations of the elements in group 7.

Q.19. (i) If an element has a low ionization energy then it is likely to be ----- [metallic/non-metallic].
(ii)If an element has seven electrons in its outermost shell then it is likely to have the ------------ [largest/smallest] atomic size among all the elements in the same period.

Q. 20. (i) The metal of Group 2 from top to bottom are : Be, Mg, Ca, Sr, Ba. Which of these metals will form ions most readily and why.
(ii) What property of an element is measured by electronegativity.

ICSE Chemistry WORK SHEET

Class X CHAPTER: HCL By SOUVIC JATI 9831497662

souvicjati@gmail.com

Q. 1. From the list given below choose the compounds whose aqueous solution give white precipitate with dilute HCl :
Ammonium chloride, ammonium nitrate, chlorine, dilute hydrochloric acid, iron, lead nitrate, manganese (IV) oxide, silver nitrate, sodium nitrate, sodium nitrite, sulphur.

Q. 2. State what you observe when silver nitrate solution is added to dilute hydrochloric acid?

Q. 3. What must be added to sodium chloride to obtain hydrogen chloride? Write the equation for the reaction.

Q. 4. What would you see when hydrogen chloride mixes with ammonia?

Q. 5. Hydrogen chloride dissolves in water forming an acidic solution.

Name the experiment which demonstrates that hydrogen chloride is very soluble in water.
Give three distinct tests [apart from using an indicator] you would carry out with this solution to illustrate the typical properties of an acid.

Q. 6. Write the equation for the reaction of hydrochloric acid with each of the following :

lead nitrate solution
manganese
Oxide.

Q. 7. Write the equation for :-

The preparation of hydrogen chloride from sodium chloride and sulphuric acid. State whether the sulphuric acid should be concentrated or dilute.
The reaction of hydrogen chloride with ammonia.

Q. 8. Name one lead compound that can be used to oxidize hydrogen chloride to chlorine ?

Q.9. From the following gases - NH₃, Cl2, HC_l, SO₂, select the gas that matches the description given below and answer the questions that follows : When gas C is mixed with gas B, dense white fumes are seen and there is no other product [gas B turns moist red litmus paper blue].

What is the name of gas C.
What is the name of the product of the reaction gas B and gas C.

Q. 10. What happens [state your observations] when dil. HCl is added to lead nitrate solutio ? .

Q. 11. Manganese (IV) oxide, lead (IV) oxide and red lead [Pb₃O₄] react with conc. HCl liberating chlorine.

What is the common property being shown by these metal oxides.
Write the equation for the reaction of conc. HCl with Pb₃O₄.

Q. 12. Write the observations and balanced equations for the following reaction :- Excess of ammonium hydroxide is added to a substance obtained by adding hydrochloric acid in silver nitrate solution?

Q. 13. From the gases - ammonia, hydrogen chloride, hydrogen sulphide, sulphur dioxide – Select the following :- The gas which gives a white ppt. when reacted with AgNO3 soln. acidified with dilute nitric acid ?

Q. 14. Write a balanced equation for the reaction of red lead (trilead tetraoxide) warmed with conc. HCl ?

Q. 15. A solution of hydrogen chloride in water is prepared. The following substances are added to separate portions of the solution :- Substances Added Gas evolved Odour Calcium carbonate Magnesium ribbon Manganese oxide with heating Sodium sulphide Complete the table by writing the gas evolved in each case and its odour ?

Q. 16. Write balanced equations for the following reactions :-

Copper oxide and dilute Hydrochloric acid.
Manganese
Oxide and concentrated Hydrochloric acid.

Q. 17 keeping fountain experiment in view answer the following questions

ii. Which property of hydrogen chloride is demonstrated by this experiment. iii. State the colour of the water that has entered the round-bottomed flask.

Q. 18. Select the correct compound from the list – Ammonia, Copper oxide, Copper sulphate, Hydrogen chloride, Hydrogen sulphide, Lead bromide – which matches with the description given below : This compound can be oxidized to chlorine ?

Q. 19. Write balanced chemical equation for the reaction of zinc and dilute hydrochloric acid ?

Q. 20. State what is observed when hydrochloric acid is added to silver nitrate solution.

Q. 21. Write a balanced chemical equation for the reaction of calcium bicarbonate & dil. Hydrochloric acid ?

Q. 22.Write balanced equation for the following reaction : Sodium chloride from sodium carbonate solution and dilute hydrochloric acid

Q. 23. You enter a laboratory after a Class has completed the Fountain Experiment. How will you be able to tell whether the gas used in the experiment was hydrogen chloride or ammonia ?

Q. 24. Write balanced equations for the reaction of dilute hydrochloric acid with each of the following :

Iron
Sodium hydrogen chloride
Iron iv. sulphide
Sodium sulphite
Sodium thiosulphate solution.

Q. 25. When silver nitrate solution is added to a solution of a salt, a white precipitate, insoluble in dilute nitric acid, is formed, identify the anion present in the salt.

Questions of SULPHURIC ACID BY SOUVIC SIR

Q.1.

Give equations for the following conversions:

Sulphur dioxide to Sulphur
Sulphur dioxide to sodium sulphite
sodium sulphite to Sulphur dioxide.

Write the equation for the laboratory preparation of Sulphur dioxide from sodium sulphite.

How is the SO₂ collected?
What does the method of collection tell you about the density of SO₂?
What do you see when SO₂ is bubbled through an acidified K₂Cr₂O7 solution?

Write one equation in each case to show the action of Sulphur dioxide as:

a reducing agent
an oxidizing agent
an acid anhydride.

When burning Sulphur [i.e. SO₂] reacts with H₂O, a compound is formed. Name the compound.
Give the balanced equation for reaction between SO₂ and moist Cl₂.
Write a balanced equation for: SO₂ and sodium hydroxide solution. [formation of normal salt].
What type of substance will liberate Sulphur dioxide from sodium sulphite.
(viii) Write the equation for the reaction by which Sulphur dioxide is converted into sodium sulphite.

Q. 2

Give one similarity and two differences between bleaching action of SO₂ gas and chlorine gas.
From the following gases – ammonia, chlorine, hydrogen chloride, Sulphur dioxide, select the gas that matches the description given below and answer the questions that follow: Gas A is a reducing agent which contains oxygen.
(a) What is the name of the gas A?
(b) What would you observe if gas A is bubbled through acidified potassium dichromate solution.
Write the observations and balanced equations for the reaction: A paper dipped in potassium permanganate solution is put on the mouth of a test-tube containing Sulphur dioxide gas.
From the gases – ammonia, hydrogen chloride, hydrogen sulphide, Sulphur dioxide – select the following:
(a) This gas can be oxidized to Sulphur.
(b) This gas decolourises potassium permanganate solution.
(c) This gas can be obtained by the reaction between copper and concentrated sulphuric acid.
The bleaching action of Cl₂ is permanent whereas the bleaching action of SO₂ is temporary.
(a) Give a reason why chlorine is not used to bleach silk.
(b) State the similarity in the use of Sulphur dioxide and chlorine as bleaching agent.
(c) Explain the bleaching action of Sulphur dioxide with the help of chemical equations.
(d) Why is bleaching by Sulphur dioxide only temporary.
State what is observed when Sulphur dioxide is passed through a jar containing bromine water.
Give a reason why Sulphur dioxide is used as an antichlor.

Q.3.

Name the oxide of Sulphur which reacts with water to give sulphuric acid.
In the Contact Process, the direct reaction between oxide of Sulphur and water is avoided. In this process, what does the oxide of Sulphur react with instead of water and what is the name of the product?
(a) What is the purpose of the Contact Process.
(b) Name the catalyst used in the Contact Process.
(c) Write the balanced equation for the reaction in the process which takes place in the presence of catalyst.
(a) Name the catalyst used industrially which speeds up the conversion of SO₂ and SO₃in the production of sulphuric acid in the laboratory or industrially.
(b) Write the equation for the conversion of Sulphur dioxide to Sulphur trioxide. Why does this reaction supply energy.
(c) What is the name of the compound formed between SO₃ and sulphuric acid.
State the name of the process by which H₂SO₄ is manufactured. Name the catalyst used.
Name the catalyst which helps in the conversion of Sulphur dioxide to Sulphur trioxide.
In the Contact Process for the manufacture of sulphuric acid, Sulphur trioxide is not converted to sulphuric acid by reacting it with water. Instead a two-step procedure is used. Write the equations for the two steps involved.
Name the process used for the large scale manufacture of sulphuric acid.

Q.4.

Write correctly balanced equation for the reaction between Iron and dilute sulphuric acid.
Write correctly balanced equations for the reaction of dilute sulphuric acid with each of the following
(a) Copper carbonate
(b) Lead nitrate solution
(c) Zinc hydroxide.
Write a balanced equation for the reaction between zinc and dilute sulphuric acid.
Write equation for
(a) Dilute H₂SO4 – producing H₂.
(b) Between Pb(NO3)₂ solution and dil. H₂SO4.
State the substance/s reacted with dilute or concentrated sulphuric acid to form the following gases:
(a) Hydrogen (b) Carbon dioxide.
State whether the acid used in each case is dilute or concentrated.
Write the equation for the laboratory preparation of:
(a) Sodium sulphate using dilute sulphuric acid.
(b) Lead sulphate using dilute sulphuric acid.
Write balanced equation for the reaction between
(a) Potassium hydrogen carbonate and dilute sulphuric acid.
(b) Sodium nitrate and concentrate sulphuric acid.
What do you see when concentrated sulphuric acid is added to copper sulphate-5-water.
“Concentrated sulphuric acid is used in the laboratory preparation of nitric acid and hydrochloric acid because it is ________ [less volatile / stronger] in comparison to these two acids.”
Write the equations for the laboratory preparation of the following salts using sulphuric acid.
(a) Copper sulphate from copper.
(b) Lead sulphate from lead nitrate.
Choose the property of sulphuric acid (A, B, C or D), which is relevant to each of the preparations [a] to [c]
A: Dil. acid (typical acid properties), B: Non-volatile acid, C: Oxidizing agent, D: Dehydrating agent.
(a) Preparation of hydrogen chloride.
(b) Preparation of ethane from ethanol.
(c) Preparation of copper sulphate from copper oxide.
Which property of sulphuric acid accounts for its use as a dehydrating agent.
Concentrated sulphuric acid is both an oxidizing agent and a non-volatile acid. Write one equation each to illustrate the above mentioned properties of sulphuric acid.

Q.5.

What do you observe when barium chloride solution is added to dilute sulphuric acid.
Supply the word (or words) that will make the sentence into a correct statement and rewrite the sentence. Copper sulphate crystals are dehydrated by sulphuric acid.
Explain how a reagent chosen from ammonium hydroxide, barium chloride, sodium chloride, sodium hydroxide, sulphuric acid and nitric acid enables to distinguish between the two acids mentioned therein.

Q.6.

When H₂S reacts with oxidizing agents, what substance is always a product of the reaction.
State the colour of the precipitate formed when H₂S is bubbled through copper sulphate solution.
State how you can obtain H₂S from iron (II) sulphide.
Name a gas which smells of rotten eggs.
What is observed when hydrogen sulphide gas is passed through lead acetate solution.
Select the correct compound from the list given – Ammonia, Copper oxide, Copper sulphate, Hydrogen chloride, Hydrogen sulphide, Lead bromide – which matches the description given below: The compounds smells of rotten eggs.

Q.7.

Dilute sulphuric acid will produce a white precipitate when added to a solution of :
A: Copper nitrate, B: Zinc nitrate,
C: Lead nitrate, D: Sodium nitrate.
Which of the following reactions is used to prepare sulphuryl chloride.
A: Adding conc. H₂SO₄ to a chloride.
B: Passing SO₂ through a solution of chlorine.
C: Reacting dry SO₂ and dry chlorine.
D: Reacting dil. H₂SO₄ with a solution of chlorine.
Identify the following substances (a) Gas C has a smell like rotten eggs. (b) Gas D is colourless gas which can be used as a bleaching agent. (c) Liquid E can be dehydrated to produce ethane.
Write the equation for the following reaction : Sulphur dioxide and water.
Copy and complete the following table relating to an important industrial process and its final output.

Name of process	Inputs	Catalyst	Equation for catalyzed reaction	Output
Contact process	Sulphur dioxide + oxygen

Making use only of substance given : dil. Sulphuric acid, Sodium carbonate, Zinc, Sodium sulphite, Lad, Calcium carbonate : Give equations for the reactions by which you could obtain : (a) hydrogen (b) sulphur dioxide (c) carbon dioxide (d) zinc carbonate [₂ steps required].
What property of conc. H₂SO₄ is used in the action when sugar turns black in its presence.
Write the equation for (a) dil. H₂SO₄ and barium chloride, (b) dil. H₂SO₄ and sodium sulphide.
Which property of conc. H₂SO₄ allows it to be used in the preparation of HCl and HNO3 acids.

SOLUTIONS OF SULPHURIC ACID BY SOUVIC JATI

Q1 SOLUTION

(a) 2Mg [heated] + SO₂ → ₂MgO + S.
(b) 2NaOH SO₂ → Na₂SO₃ + H₂O.
(c) Na₂SO3+ H₂SO₄ → Na₂SO₄ + H₂O + SO₂
Na₂SO3 + ₂HCl → ₂NaCl + H₂O + SO₂.
(a) Na₂SO₃ + ₂HCl → ₂NaCl + H₂O + SO₂.
(b) Sulphur dioxide is collected by upward displacement of air.
(c) Sulphur dioxide is ₂.₂ times heavier than air.
(d) When SO₂ is bubbled through acidified solution of K₂Cr₂O7, the orange colour of potassium dichromate solution turns to clear green due to formation of chromium sulphate:
K₂Cr₂O₇ + H₂SO₄ + 3SO₂ → Cr₂(SO₄)₂ + H₂O.
(a) 2HNO₃ + SO₂ → ₂NO₂ + H₂SO₄.
(b) 2Mg [heated] + SO₂ → ₂MgO + S.
(c) H₂O + SO₂ → H₂SO₃.
sulphurous acid.
SO₂ + Cl₂ + ₂H₂O → ₂HCl + H₂SO₄.
2NaOH + SO₂ → Na₂SO₃ + H₂O.
Any mineral acid HCl, H₂SO₄ or HNO₃.
Na₂O + SO₂ → Na₂SO₃.

QUESTION 2 Ans.

	Chlorine	Sulphur dioxide
Similarity : Presence of moisture is essential for bleaching.	Cl₂ + H₂O → HCl + HOCl	SO₂ + ₂H₂O → H₂SO₄ + [H]
Dissimilarity	1. Bleaches by oxidation.	1. Bleaches by reduction.
	2. Bleaching is permanent.	2. Bleaching is temporary.
	3. Strong bleaching agent.	3. Mild bleaching agent.

Sulphur dioxide.
Orange coloured acidified potassium dichromate solution changes to green.
Pink colour of paper is disappeared.
₂KMnO₄ + ₂H₂O + 5SO₂ → ₂MnSO₄ + K₂SO₄ + ₂H₂SO₄.
Hydrogen sulphide.
Sulphur dioxide.
Sulphur dioxide.
Chlorine damages the silk.
Both act as bleaching agents in presence of moisture.
SO₂ (g) + ₂H₂O → H₂SO₄ (aq.) + ₂[H]
₂[H] + colouring matter → Colourless matter.
Because oxygen present in air oxidizes the reduced dye.
Red colour of bromine water disappears.
Sulphur dioxide acts as a reducing agent, reduces halogens to hydrogen halides.
SO₂ + ₂H₂O + Cl₂ → ₂HCl + H₂SO₄

Ans. 3

Sulphur trioxide.
Concentrated sulphuric acid. Oleum or Pyrosulphuric acid.
(a) To manufacture sulphuric acid.
(b) Vanadium pentaoxide or platinised asbestos.
(c) V₂O₂
₂SO₂ + O₂ → ₂SO₃
450ºC
(a) Vanadium pentaoxide or platinised asbestos.
(b) V₂O₂
₂SO₂ + O₂ → ₂SO₃
450ºC
The reaction supplies energy as the reaction is exothermic in nature.
(c) Oleum or Pyrosulphuric acid.
H₂SO₄ is manufactured by Contact Process. The catalyst used in the process is Vanadium pentaoxide or Platinised asbestos.
Vanadium pentaoxide or Platinised asbestos.
SO₃ + H₂SO₄ → H₂S₂O₇ (Oleum).
H₂S₂O₇ + H₂O → ₂H₂SO₄.
Contact Process.

Ans. 4

Fe + H₂SO₄ (dil.) → FeSO₄ + H₂.
(a) CuCO₃ + H₂SO₄ (dil.) → CuSO₄ + H₂O + CO₂.
(b) Pb(NO₃)₂ + H₂SO₄ (dil.) → PbSO₄ ↓ + ₂HNO₃.
(c) Zn(OH)₂ + H₂SO₄ (dil.) → ZnSO₄ + ₂H₂O.
Zn + H₂SO₄ (dil.) → ZnSO₄ + H₂.
(a) Zn + H₂SO₄ (dil.) → ZnSO₄ + H₂.
(b) Pb(NO₃)₂ + H₂SO₄ (dil.) → PbSO₄ ↓ + ₂HNO₃.
(a) Active metals like Zn or Fe with dilute sulphuric acid.
(b) Carbonates or bicarbonates of metals with dilute sulphuric acid.
(a) Na₂O + H₂SO₄ (dil.) → Na₂SO₄ + H₂O.
₂NaOH + H₂SO₄ (dil.) → Na₂SO₄ + ₂H₂O.
Na₂SO₃ + H₂SO₄ (dil.) → Na₂SO₄ + H₂O + SO₂.
₂NaHSO₃ + H₂SO₄ (dil.) → Na₂SO₄ + ₂H₂SO₄ + ₂SO₂.
(b) Pb(NO₃)₂ + H₂SO₄ (dil.) → ₂HNO₃ + PbSO₄ ↓
(a) ₂KHCO₃ + H₂SO₄ (dil.) → K₂SO₄ + ₂H₂O + ₂CO₂.
(b) NaNO₃ + H₂SO₄ (conc.) → NaHSO₄ + HNO₃ (vap.)
H₂SO4
CuSO4.5H₂O → CuSO₄ + 5H₂O.
[blue hydrous] [conc.] [white anhydrous]
Less volatile.
(a) Cu + ₂H₂SO₄ (conc.) → CuSO₄ + ₂H₂O + SO₂.
(b) Pb(NO₃)₂ + H₂SO₄ → ₂HNO₃ + PbSO4 ↓.
(a) B (non-volatile acid). (b) D (dehydrating agent). (c) A (dilute acid).
Sulphuric acid’s high affinity for water accounts for its use as a dehydrating agent.
Oxidizing agent :
S + ₂H₂SO₄ (conc.) → 3SO₂ + ₂H₂O.
Non volatile acid :
₂NaNO₃ + H₂SO₄ (conc.) → Na₂SO4 + ₂HNO₃.

Ans. Q5

A white precipitate of barium sulphate is formed which is insoluble in all mineral acids.
Blue hydrous copper sulphate turns into white anhydrous copper sulphate due to removal of water of crystallization by concentrated sulphuric acid.
With BaCl₂ solution, sulphuric acid will give white precipitate while nitric acid will not give any precipitate.

Ans. Q6

Sulphur.
Black precipitate of CuS.
CuSO₄ + H₂S → CuS ↓ + H₂SO₄.
Hydrogen sulphide is obtained by the action of dilute H₂SO₄ on iron (II) sulphide.
Hydrogen sulphide.
hen hydrogen sulphide gas is passed through lead acetate solution, black coloured precipitate of lead sulphide is formed.
Pb(CH₃COO)₂ + H₂S → PbS ↓ + ₂CH₃COOH.
Hydrogen sulphide.

Ans : Q7

C : Lead nitrate.
C: Reacting dry SO₂ and dry chlorine.
(a) C is hydrogen sulphide (b) D is sulphur dioxide (c) E is ethanol.
SO₂ + H₂O → H₂SO₃.

Name of process	Inputs	Catalyst	Equation for catalyzed reaction	Output
Contact process	Sulphur dioxide + oxygen	V₂O₅ or Pt	₂SO₂ + O₂ → ₂SO3+ ∆	H₂SO₄

(a) Zn + H₂SO₄ → ZnSO₄ + H₂ (b) Na₂SO₃ + H₂SO₄ → Na₂SO₄ + H₂O + SO₂ (c) Na₂CO₃ + H₂SO₄ → Na₂SO₄ + H₂O + CO₂ (d) Zn + H₂SO₄ → ZnSO₄ + H₂O + SO₂
ZnSO4 + CaCO3 → ZnCO3 + CaSO4.
Dehydrating agent.
(a) BaCl₂ + H₂SO₄ → BaSO₄↓ + ₂HCl
(b) Na₂S + H₂SO₄ → Na₂SO₄ + H₂S
Less volatile or non-volatile acid with a high boiling point.

11 comments:

xx20 January 2016 at 22:41
students please find the documents in different subjects.
Unknown22 January 2016 at 07:50
sir the answers of periodic table and HCl is not there
Unknown22 January 2016 at 18:03
Sir there is no paper to solve in physics and mathematics

Observe23 January 2016 at 07:01
This comment has been removed by the author.
Unknown23 January 2016 at 22:51
Sir organic chemistry, nitric acid,ammonia, metallurgy and electrolysis are missing.
Unknown10 March 2016 at 00:08
sir this was very helpful!!
Unknown20 November 2017 at 04:05
thank you!
Unknown14 December 2017 at 08:48
Sir, Metallurgy is missing
alfachemistry8 August 2018 at 12:10
We make the custom synthesis process more efficient and cost effective while maintaining the highest standards of quality and reliability. ACID ORANGE 51

IA	2A	1B	2B	3B	4B	5B	6B	7B	8	8	8	3A	4A	5A	6A	7A	0
l																	2
H																	He
3	4											5	6	7	8	9	10
LI	Be											B	C	N	O	F	Ne
II	12											13	14	15	16	17	18
Na	Mg											Al	SI	P	S	Cl	Ar
19	20	21	22	23	24	25	26	27	28	29	30	31	32	33	34	35	36

IA	2A	1B	2B	3B	4B	5B	6B	7B	8	8	8	3A	4A	5A	6A	7A	0
l																	2
H																	He
3	4											5	6	7	8	9	10
LI	Be											B	C	N	O	F	Ne
II	12											13	14	15	16	17	18
Na	Mg											Al	SI	P	S	Cl	Ar
19	20	21	22	23	24	25	26	27	28	29	30	31	32	33	34	35	36

IA	2A	1B	2B	3B	4B	5B	6B	7B	8	8	8	3A	4A	5A	6A	7A	0
l																	2
H																	He
3	4											5	6	7	8	9	10
LI	Be											B	C	N	O	F	Ne
II	12											13	14	15	16	17	18
Na	Mg											Al	SI	P	S	Cl	Ar
19	20	21	22	23	24	25	26	27	28	29	30	31	32	33	34	35	36