Question

Which of the following does not react with sodium hydroxide to liberate hydrogen gas?​

Answer 1

Answer:

Two metals which react with concentrated sodium hydroxide solution to liberate hydrogen gas are Zinc (Zn) and Aluminium(Al).

Answer 2

$CH_3CHO$ or Ethanal does not react with $NaOH$ or Sodium Hydroxide to liberate Hydrogen Gas.

This is because Aldehydic Group does not have any Acidic Hydrogen which can be liberated as Hydrogen gas on reaction with Sodium Metal whereas its other counterparts like Ethanol, and Ethanoic Acid all have Acidic Hydrogen.

$R-H + Na - > RNa + H_2$

(Reaction of Sodium Metal and Compound containing acidic $H_2$)