When a black metal compound XO is heated with a colourless gas `Y_(2)` , then metal X and another compound `Y_(2)O` are formed. Metal X is red-brown in colour which does not react with dilute acids at all. Gas `Y_(2)` can be prepared by the action of a dilute acid on any active metal. The compound `Y_(2)O` is a liquid at room temperature which can turn anhydrous copper sulphate blue.
(a) What do you think is metal X ?
(b) What could be gas `Y_(2)`
(c) What is compound `XO` ?
(d) What is compound `Y_(2)O`
(e) Write the chemical equation of the reaction which takes place on heating XO with `Y_(2)`.
(f) What type of chemical recation is illustrated in the above equation.

Answer

(a) Copper (Cu) (b) Hydrogen `(H_(2))` (c) Copper oxide (CuO) (d) Water `(H_(2)O)` (e) CuO `+ H_(2) to Cu + H_(2)O` (f) Displacement reaction (which is also a redox reaction)