Fill in the blank from the choices in the bracket :

Quicklime is not used to dry HCl gas because …………… [CaO is alkaline, CaO is acidic, CaO is neutral]

Write the balanced equation for:
Action of dilute hydrochloric acid on sodium sulphide.

Study the figure given below and answer the questions that follow :

(i) Identify the gas Y.

(ii) What property of gas Y does this experiment demonstrate?

(iii) Name another gas which has the same property and can be demonstrated through this experiment.

Select from the gases — ammonia, ethane, hydrogen chloride, hydrogen sulphide, ethyne — The gas which produces dense white fumes with ammonia gas.