Write the structural formulae of the three derivatives of monocarboxylic acid. Identify the functional group present in them.

Explanation

The three derivatives of monocarboxylic acids are
Amides `underset("Primary amide")(R-oversetoverset(O)(||)(C)-NH_(2)),underset("Secondary amide")(R-oversetoverset(O)(||)(C)-NHR),underset("Tertiary amide")(R-oversetoverset(O)(||)(C)-NR_(2))`
Acid chlorides `R-oversetoverset(O)(||)(C)-Cl`
Esters `R-oversetoverset(O)(||)(C)-OR`., where R, R. are alkyl grops.
The functional group present in these derivatives are
Amides `-oversetoverset(O)(||)(C)-NH_(2)` Acid chlorides `-oversetoverset(O)(||)(C)-Cl`
Esters `-oversetoverset(O)(||)(C)-OR.`