Question

Sodium hydroxide is taken in place of dilute sulphuric acid and the tube is heated then which gas will be evolved?

Answer 1

The reaction of Zn with sulphuric acid can be written as-

$H_{2}S{O}_4\left(aq\right)+Zn\left(s\right)⟶ZnS{O}_4\left(aq\right)+H_2\left(g\right)$

Sodium hydroxide is taken in place of dilute sulphuric acid and the tube is heated then the reaction that takes place can be written as follows.

$2NaOH\left(aq\right)+Zn\left(s\right)⟶N{a}_{2}Zn{O}_2\left(aq\right)+H_2\left(g\right)$

(Sodium zincate )

Here, hydrogen is formed in the reaction. However, such reactions are not possible with all metals.

So, hydrogen is the correct answer.