Chemistry — Suggested Paper 3

1(i). Identify the equation that shows the reaction of ethane with chlorine in the presence of ultraviolet light.

1(ii). An element in period 3, whose electron affinity is zero:

1(iii). Which of the following reactions takes place at the anode during the electroplating of an article with silver?

1(iv). If Relative Molecular Mass of Butane (C₄H₁₀) is 58 then its vapour density will be:

1(v). The compound that is not a constituent of the electrolytic mixture used in the Hall-Heroult's process is:

1(vi). The products formed when an acid reacts with a base is:

1(vii). Vanadium pentoxide is used as a catalyst in the preparation of:

1(viii). Which one of the following is a non-metallic cation?

1(ix). The metallic hydroxide which forms a deep inky blue solution with excess ammonium hydroxide solution is:

1(x). The aim of the Fountain Experiment is to prove that:

1(xi). Ammonia gas is collected by downward displacement of air since ammonia is:

1(xii). The metal whose oxide can be reduced by common reducing agents:

1(xiii). If an element has low ionization potential, then it is likely to be a:

1(xiv). Which apparatus could be used to electroplate an iron nail with copper?

1(xv). An organic compound has a vapour density of 22. The molecular formula of the organic compound is: [Atomic weight: C = 12, H = 1]

2(i)(i). Action of cold and dilute Nitric acid on Copper.

2(i)(ii). Reaction of Ammonia with heated copper oxide.

2(i)(iii). Preparation of methane from iodomethane.

2(i)(iv). Action of concentrated sulphuric acid on Sulphur.

2(i)(v). Laboratory preparation of ammonia from ammonium chloride.

2(ii)(i). Reaction of carbon powder and concentrated nitric acid.

2(ii)(ii). Reaction of excess ammonia with chlorine.

2(ii)(iii). Reaction of lead nitrate solution with ammonium hydroxide.

2(ii)(iv). Producing ethane from bromo ethane using Zn/Cu couple in alcohol.

2(ii)(v). Complete combustion of ethane.

2(iii)(a). Name the constituent of the electrolyte mixture which has a divalent metal in it.

2(iii)(b). Name the powdered substance 'X' sprinkled on the surface of the electrolyte mixture.

2(iii)(c). What is the name of the process?

2(iii)(d). Write the reactions taking place at the electrodes 'Y' (anode) and 'Z' (cathode) respectively.

2(iv)(i). Sulphur is oxidized by concentrated nitric acid.

2(iv)(ii). Action of dilute hydrochloric acid on sodium sulphide.

2(iv)(iii). Action of cold and dilute nitric acid on copper.

2(iv)(iv). At the anode during the electrolysis of acidified water.

2(iv)(v). Reaction of ethanol and sodium.

2(v). Match the Column A with Column B:

3(i)(a). Electronegativity

3(i)(b). Gay-Lussac's Law of combining volumes

3(ii). The Empirical formula of an organic compound is CHCl₂ If its relative molecular mass is 168, what is its molecular formula? [At. Wt. C = 12, H = 1, Cl = 35.5]

3(iii)(a). The metal that will not produce hydrogen gas when reacted with dilute acids.

3(iii)(b). The compound that will produce sulphur dioxide gas when reacted with dilute HCl.

3(iii)(c). The solution of this compound produces dirty green precipitate with NaOH.

3(iv)(a). To the copper nitrate solution, initially few drops of sodium hydroxide solution is added and then added in excess.

3(iv)(b). Burning of ammonia in excess of oxygen.

3(iv)(c). Dry ammonia gas is passed over heated PbO.

4(i)(a). Name the type of oxide represented in region X in the diagram.

4(i)(b). Identify the oxide which has been incorrectly placed in the above diagram.

4(i)(c). Name the oxide from the above diagram which will form an alkali when dissolved in water.

4(ii)(a). Which compound forms a single product with bromine?

4(ii)(b). Which two compounds have the same molecular formula?

4(ii)(c). Which two compounds will react together in the presence of concentrated H₂SO₄ to form a product with a fruity smell?

4(iii). An organic compound ‘X’ contains carbon, oxygen and hydrogen only. The percentage of carbon and hydrogen are 47.4% and 10.5% respectively. The relative molecular mass of ‘X’ is 76. Find the empirical formula and the molecular formula of ‘X’. [Atomic weight: C = 12, O = 16, H = 1]

5(a)(i). Complete the following table which relates to the homologous series of hydrocarbons.

5(b)(i). Name the most common ore of the metal aluminum from which the metal is extracted. Write the chemical formula of the ore.

5(b)(ii). Name the process by which impure ore of aluminum gets purified by using concentrated solution of an alkali.

5(b)(iii). Write the equation for the formation of aluminum at the cathode during the electrolysis of alumina.

6(a)(i). Conductor and electrolyte (conducting particles)

6(a)(ii). Cations and anions (formation from an atom)

6(a)(iii). Acid and Alkali (formation of type of ions)

6(b). Draw the structures of isomers of pentane.

6(c)(i). Give the balanced chemical equation for the reaction with suitable condition(s) if any.

6(c)(ii). Why is concentrated sulphuric acid used instead of concentrated nitric acid?

6(c)(iii). How is the gas collected?

6(c)(iv). Name the drying agent not used for drying the gas.

7(a)(i). Lead nitrate solution and Zinc nitrate solution

7(a)(ii). Sodium chloride solution and Sodium nitrate solution

7(b)(i). Copper sulphate from Copper carbonate.

7(b)(ii). Zinc carbonate from Zinc sulphate.

7(c)(i). What is the type of salt formed when the reactants are heated at a suitable temperature for the preparation of Nitric acid?

7(c)(ii). State why for the preparation of Nitric acid, the complete apparatus is made up of glass.

7(d)(i). Ethanol?

7(d)(ii). Carbon?

8(a)(i). The catalyst used to oxidise ammonia.

8(a)(ii). The organic compound which when solidified, forms an ice like mass.

8(a)(iii). The dilute acid which is an oxidizing agent.

8(b)(i). What mass of copper hydroxide is precipitated by using 200 g of sodium hydroxide. [H = 1, O = 16, Na = 23, S = 32, Cu = 64]

8(b)(ii). What is the colour of the precipitate formed.

8(c). Find the empirical formula and the molecular formula of an organic compound from the data given below: C = 75.92%, H = 6.32% and N = 17.76% The vapour density of the compound is 39.5. [C = 12, H = 1, N = 14]