What property of hydrogen chloride is demonstrated when it is collected by downward delivery [upward displacement]. Why is hydrogen chloride not collected over water.

Match each substance A to E listed below with the appropriate description given below :

[A] Sulphur
[B] Silver chloride
[C] Hydrogen chloride
[D] Copper [II] Sulphate
[E] Graphite.

(i) A covalent compound which behaves like an ionic compound in aqueous solution.
(ii) A compound which is insoluble in cold water but soluble in excess of ammonia solution.

Write equations for the reaction of dil. HCl with each of the following :

(i) iron

(ii) sodium hydrogen carbonate

(iii) iron [II] sulphide

(iv) sodium sulphite

Name the gas evolved - The gas produced by the action of concentrated sulphuric acid on sodium chloride.