Question

Statement I:- Hydrogen gas is not evolved when zinc reacts with cold water.

Statement II:- Sodium reacts vigorously with cold water to produce sodium hydroxide and hydrogen gas.

• A. Only statement I is true.
• B. Only statement II is true.
• C. Both statements are true.
• D. Both statements are false.

Answer 1

The correct option is C Both statements are true.

Zinc does not react with cold water to produce hydrogen gas. It produces hydrogen gas on reacting with steam. The reaction involved is:

$\text{Zn(s)}+2{\text{H}}_2\text{O(l)}\to {\text{Zn(OH)}}_2\text{(aq)}+{\text{H}}_2\text{(g)}$

Sodium reacts vigorously with cold water to produce sodium hydroxide and hydrogen gas. The reaction involved is:

$2\text{Na(s)}+2{\text{H}}_2\text{O(l)}\to 2\text{NaOH(aq)}+{\text{H}}_2\text{(g)}$