C6H5, also known as the phenyl group, is a functional group derived from benzene. It consists of six carbon atoms arranged in a ring, with five hydrogen atoms attached to the carbon atoms. The phenyl group is often represented as "Ph" in chemical formulas and is commonly found in various organic compounds. The phenyl group plays a significant role in organic chemistry, as it can influence the properties and reactivity of molecules. It is a key component in many important compounds, including aniline, phenol, and various pharmaceuticals, contributing to their chemical behavior and applications.