Question

When same amount of zinc is treated separately with excess of sulphuric acid and excess of sodium hydroxide solution, the ratio of volumes of hydrogen evolved is:

• A. 1:01
• B. 1:02
• C. 2:01
• D. 9:04

Answer 1

Answer: (A)

1:01

Answer 2

The reactions of zinc with sulphuric acid and excess of sodium hydroxide separately are given below:
$Zn +2 NaOH \rightarrow Na _{2} ZnO _{2}+ H _{2}$
$Zn + H _{2} SO _{4} \rightarrow ZnSO _{4}+ H _{2}$
In both the reactions, $1$ mole of $H _{2}$ is evolved.
Hence, the ratio of volumes of hydrogen evolved is $1: 1$.