Chemistry Regents Practice Test 2025 – 400 Free Practice Questions to Pass the Exam

A saturated hydrocarbon is characterized by having only single bonds between carbon atoms. This allows the maximum number of hydrogen atoms to be attached to the carbon skeleton, which is why they are called "saturated." Saturated hydrocarbons, such as alkanes, have the general formula CnH(2n+2).

In contrast, unsaturated hydrocarbons contain one or more double or triple bonds between carbon atoms, which means they do not have the maximum number of hydrogen atoms attached. This difference in bonding affects their chemical properties and reactivity. For example, unsaturated hydrocarbons can undergo reactions such as addition reactions due to the presence of these multiple bonds, while saturated hydrocarbons are generally more stable and less reactive.

The other options, which mention gas state and boiling points, pertain more to the physical properties and states of different hydrocarbons rather than the specific structural characteristics that define saturation versus unsaturation.