It can be a compound or a single element. An element is a pure substance that cannot be separated into simpler substances by chemical or physical means. There are about 117 elements, but carbon, hydrogen, nitrogen and oxygen are only a few that make up the largest portion of Earth.
I would say pure substances
<span>Saturated hydrocarbon cannot bond with compounds anymore, where as unsaturated hydrocarbons can bond, as they contain double or triple bonds. When they bond, the double and triple bonds break and new separate single bonds are formed with hydrogens or any other external compounds</span>
