Question

Give a reason why metals are arranged in a series called – ‘activity series of metals’. Name a metal which reacts with

(a) Cold water
(b) Boiling water
(c) Steam to liberate hydrogen in each case.

Answer 1

Metals arranged in series are called ‘activity series of metals’ because metals differ in tendency to lose valence electrons and can be arranged in a series, i.e. metals are arranged in decreasing order of their reactivity. The most reactive metal at top of the series and then with decreasing reactivity.

Metal that reacts with
(a) Cold water – Sodium

2Na + 2H₂O → 2NaOH + H₂

(b) Boiling water – Magnesium [Mg]
(c) Steam – Iron [Fe]