Question

You are given the following materials :

(i) Iron nails

(ii) Copper sulphate solution

(iii) Barium chloride solution

(iv) Copper powder

(v) Ferrous sulphate crystals

(vi) Quick lime.
Identify the type of chemical reaction taking place and also write down their chemical equation when :

(a) Barium chloride solution is mixed with copper sulphate solution and a white precipitate is observed.
(b) On heating, copper powder in air in a china dish, the surface of copper powder becomes black.
(c) On heating green ferrous sulphate crystals, reddish brown solid is left and a gas having smell of burning

sulphur is noticed.
(d) Iron nails when left dipped in blue copper sulphate solution become brownish in colour and blue colour

of copper sulphate solution fades away. (e) Quick lime reacts vigorously with water releasing a large amount of heat.​

Answer 1

Answer:

☞An aqueous solution of barium chloride is mixed with an aqueous solution of copper (II) sulfate. Formation of white precipitate indicates that it is barium sulfate implying the presence of SO 4 2- . The barium sulfate precipitates to form a white solid. The solubility product constant for barium sulfate is 1.1 x 10-10.

☞When the copper powder is heated in a china dish the copper powder surface becomes coated with black colour substance due to the formation of copper oxide by surface oxidation. The black colour is due to the formation of this copper (II) oxide as the copper comes in contact with the air.

☞When green coloured crystals of ferrous sulphate (FeSO4) is heated , it decomposes to form Ferric Oxide (Fe2O3) ,sulphur trioxide (SO3) and sulphur dioxide( SO2) . The sulphur dioxide gas gives the odour smell. This Reaction is an example of Thermal Decomposition Reaction.

☞Fe+CuSO4= FeSO4+Cu. Iron as it is highly reactive than copper replaces it . So the blue colour of copper sulphate fades away.

Explanation:

$\huge\frak\purple{@PreciousLily}$