What kind of ion is formed when metals lose protons?

When metals lose protons, they form cations. In the context of chemistry, cations are positively charged ions that occur when an atom loses one or more electrons. While metals have a relatively low ionization energy, which allows them to easily lose these electrons, protons are not typically lost in this process since protons are found in the nucleus of the atom and do not participate in bonding or ionic formation in the same way that electrons do.

The formation of a cation occurs when a neutral metal atom loses an electron, resulting in a net positive charge. An example would be sodium (Na), which loses an electron to become Na⁺. Cations are essential in forming ionic bonds with anions, which are negatively charged ions. This concept is crucial in understanding chemical reactions, bonding, and electric charge in various compounds.

Other options, such as anions, polyatomic ions, and molecules, involve different processes and types of bonding. Anions, for instance, are formed when an atom gains electrons, leading to a negative charge. Polyatomic ions consist of multiple atoms bonded together that carry a net charge. Molecules, on the other hand, are formed when atoms share electrons through covalent bonds but do not involve changes in charge