Question

Which of the following is true about the preparation of hydrogen gas?

• A. Hydrogen is produced by the action of mineral acids on highly reactive metals like sodium and potassium
• B. Hydrogen is produced by the action of mineral acids on moderately reactive metals like iron and aluminium
• C. Hydrogen is produced by the action of mineral acids on low reactive metals like gold and silver
• D. Hydrogen is NOT produced by the action of mineral acids on any metals.

Answer 1

Answer: (A), (B)

The correct options are
A

Hydrogen is produced by the action of mineral acids on highly reactive metals like sodium and potassium

B

Hydrogen is produced by the action of mineral acids on moderately reactive metals like iron and aluminium

Hydrogen is produced by the action of mineral acids on highly reactive metals.
$2Na\left(s\right)+2HCl\left(aq\right)⟶2NaCl\left(aq\right)+H_2\left(g\right)$
Hydrogen is produced by the action of mineral acids on moderately reactive metals.
$Mg\left(s\right)+2HC{l}_{a}q)⟶MgC{l}_2(aq)+H_2(g)$
Metals which lie above hydrogen in activity series displace hydrogen gas from mineral acids. Since silver and gold are below hydrogen in the activity series, mineral acids do not react with silver and gold to produce hydrogen gas.