What is one characteristic of saturated hydrocarbons?

Saturated hydrocarbons are defined by their structure, which consists solely of single bonds between carbon atoms. This means that each carbon atom is bonded to the maximum number of hydrogen atoms possible. The absence of double or triple bonds is what distinguishes saturated hydrocarbons from unsaturated hydrocarbons, which do have one or more multiple bonds.

By having only single bonds, saturated hydrocarbons tend to be more stable and less reactive compared to unsaturated hydrocarbons. This stability arises because single bonds are generally stronger and require more energy to break than double or triple bonds. As a result, the characteristic of containing only single bonds is central to the identity of saturated hydrocarbons.

In contrast, the other options describe different types of hydrocarbons or characteristics unrelated to saturation. Multiple bonds indicate the presence of unsaturation, being liquids at room temperature is not specific to saturation and can apply to various hydrocarbons, and higher reactivity is also typical of unsaturated hydrocarbons due to the presence of these multiple bonds. Thus, the defining feature of saturated hydrocarbons is their single-bonded structure.