Question

Formic acid and formaldehyde can be distinguished by treating with

Answer 1

Treat both Formic acid and Formaldehyde with NaHCO₃( sodium bicarbonate)

Formic acid liberates CO₂ on reaction with NaHCO₃ while formaldehyde doesn't.

This way both of them can be easily distinguished.

Answer 2

Explanation;

In order to distinguish formaldehyde from formic acid we will perform Iodoform test.

The carbonyl compounds containing $CH_3CO-$ group when reacts with iodine gas in the presence of alkali results in formation of Iodofrom.

• formaldehyde will give yellow color iodoform.

$CH_3CHO+3I_2+3NaOH\rightarrow CI_3CHO+3NaI+3H_2O$

$CI_3CHO+\overset{H_2O/NaOH}\rightarrow CHI_3(yellow)+HCOONa$

• Formic acid will not give this test.

$HCOOH+3I_2+3NaOH\rightarrow$ No reaction