Which group of atoms is denoted by the formula NH2?

The formula NH2 represents an amino group, which consists of a nitrogen atom bonded to two hydrogen atoms. This functional group is fundamental in organic chemistry, particularly in amino acids, which are the building blocks of proteins. The presence of the amino group is crucial for the properties of amino acids, as it contributes to both their basicity and their ability to participate in peptide bonding during protein synthesis.

In contrast, the carbonyl group, hydroxyl group, and carboxyl group each have distinct structural formulas and functions. The carbonyl group contains a carbon atom double-bonded to an oxygen atom, while a hydroxyl group consists of an oxygen atom bonded to a hydrogen atom. The carboxyl group combines both a carbonyl and a hydroxyl group. Understanding the unique characteristics of the amino group helps clarify its importance in biochemical processes.