State one relevant observation for each of the following : (i) When c

1.	State one relevant observation for each of the following : (i) When crystals of copper nitrate are heated in a test tube. (ii) When the gaseous product obtained by dehydration of ethyl alcohol is passed through bromine water. (iii) Wen hydrogen sulphide gas is passed through lead acetate solution. (iv) When ammonia gas is burnt in an atmosphere of excess oxygen. (v) At the Anode when aqueous copper sulphate solution is electrolysed using copper electrodes.
Answer» (i) The blue coloured copper nitrate crystals changes into black powdery mass with the release of reddish brown NO₂ gas. (ii) The reddish brown colour of bromine water disappears. (iii) Lead acetate solution becomes black due to the formation of lead sulphide. (iv) Ammonia burns with a yellowish green flame in the atmosphere of excess oxygen. (v) The copper of the anode dissolves and, therefore, it becomes thin gradually.

State one relevant observation for each of the following : (i) When crystals of copper nitrate are heated in a test tube. (ii) When the gaseous product obtained by dehydration of ethyl alcohol is passed through bromine water. (iii) Wen hydrogen sulphide gas is passed through lead acetate solution. (iv) When ammonia gas is burnt in an atmosphere of excess oxygen. (v) At the Anode when aqueous copper sulphate solution is electrolysed using copper electrodes.

Answer»

(i) The blue coloured copper nitrate crystals changes into black powdery mass with the release of reddish brown NO₂ gas.

(ii) The reddish brown colour of bromine water disappears.

(iii) Lead acetate solution becomes black due to the formation of lead sulphide.

(iv) Ammonia burns with a yellowish green flame in the atmosphere of excess oxygen.

(v) The copper of the anode dissolves and, therefore, it becomes thin gradually.