Which particle in an atom carries a negative charge?

The particle in an atom that carries a negative charge is the electron. Electrons are fundamental subatomic particles that orbit the nucleus of an atom, which contains positively charged protons and neutrally charged neutrons. Electrons have a charge of -1, indicating their negative nature. Their role in chemical reactions and bonding is vital, as they are involved in the formation of bonds between atoms and contribute to an atom's overall charge when counting protons and electrons.

Protons, in contrast, carry a positive charge and are located in the nucleus, while neutrons have no charge and also reside in the nucleus, contributing to the atomic mass. A positron is the antiparticle of an electron, possessing a positive charge and is not found under normal circumstances within an atom. Thus, among the given options, the electron is uniquely characterized by its negative charge.