What is ion ? And when was it discovered?

Answer 1

The atoms and molecules are neutral. This means that the number of electrons (charged negatively) is equal to the number of protons charged positively. If an atom or a molecule has one electron more than the number of protons it becomes an ion with a negative charge called anion . Inversely if an atom or a molecule looses an electron it becomes an ion charged positively or cathion.

The electricity was discovered long before we knew the structure of atoms.

Answer 2

An ion is an atom which has an imbalance in the number of protons and electrons, resulting in a net electric charge. This electric charge allows these atoms to bind with other atoms with similar but opposite charges to form molecular compounds.