Chemistry Regents Practice Test 2025 - Free Chemistry Regents Practice Questions and Study Guide

Saturated hydrocarbons are characterized by having only single bonds between the carbon atoms in their molecular structure. This means that each carbon atom is bonded to the maximum number of hydrogen atoms possible, following the tetravalence rule, where each carbon atom can form four bonds. As a result, saturated hydrocarbons typically are found in the form of alkanes.

The presence of only single bonds indicates that these molecules are fully 'saturated' with hydrogen. In contrast, unsaturated hydrocarbons, such as alkenes and alkynes, contain at least one double or triple bond between carbon atoms, which decreases the number of hydrogen atoms that can attach to the molecule. This distinction between single and multiple bonds is fundamental in organic chemistry and significantly affects the chemical behavior and reactivity of these two types of hydrocarbons.

Thus, the statement that saturated hydrocarbons contain only single bonds accurately reflects their structural composition, making it the correct answer.