Question

Formamide is
A.$HCON{{H}_{2}}$
B.$C{{H}_{3}}CON{{H}_{2}}$
C.$HCOON{{H}_{4}}$
D.$(HCHO+N{{H}_{3}})$

Answer 1

Hint: Formamide is the simplest monocarboxylic acid amide. It can be synthesized by formal condensation of formic acid and ammonia and it is functionally related to formic acid. To approach this problem we will have to the general structure of the carboxylic acid amide compound.

Complete answer:Generally, amides are derived from carboxylic acids in which the hydroxyl part $(-OH)$is replaced by $-N{{H}_{2}}$ group. For example, a general carboxylic acid, $RCOOH$reacts with ammonia, $N{{H}_{3}}$to form an amide-containing $-CON{{H}_{2}}$group.

$RCOOH+N{{H}_{3}}\to RCON{{H}_{2}}+{{H}_{2}}O$

The structure of amide is shown below:


The naming of amide is derived from the carboxylic acid by replacing the ‘’oic acid’’ ending with the word ‘’amide’’.

For example, the chemical formula of formic acid is $HCOOH$and the amide corresponding to formic acid is methanamide,$HCON{{H}_{2}}$.Similarly methanoic acid $C{{H}_{3}}COOH$and its corresponding amide are ethanamide, $C{{H}_{3}}CON{{H}_{2}}$.

As we can see over here that $-CON{{H}_{2}}$groups are present in (A) and (B), so both are compounds of amide in which (A) $HCON{{H}_{2}}$is methanamide (one carbon atom is present) or formamide and (B) $C{{H}_{3}}CON{{H}_{2}}$is ethanamide( two carbon atoms are present).


In (C) $HCOON{{H}_{4}}$is not an amide but an ammonium salt of formic acid.

When formaldehyde, $HCHO$reacts with ammonia, $N{{H}_{3}}$it forms hexamethylenetetramine, ${{(C{{H}_{2}})}_{6}}{{N}_{4}}$ popularly known as urotropine. Hence it is also not an amide compound.

$6HCHO+4N{{H}_{3}}\to {{(C{{H}_{2}})}_{6}}{{N}_{4}}+6{{H}_{2}}O$

Therefore the correct chemical formula of formamide is $HCON{{H}_{2}}$.

Thus, option (A) is correct.

Note: Formamide has many industrial chemical applications in the field of the pharmaceutical industry. It can also be used in the production of papers and can dissolve compounds and form ions, therefore it can be used as a solvent. This is a very toxic chemical to cause birth defects, so women should avoid this chemical in the early stages of pregnancy.