Bonds & ions
Ion — আয়ন
Quick answer
An ion is an atom or molecule that has lost or gained electrons, so it carries a net positive or negative charge.
Definition
An ion is an atom, or a group of atoms, in which protons and electrons are unequal in number, giving it a net electric charge. Losing electrons leaves more protons than electrons, so the atom becomes a positive ion or cation; gaining electrons makes a negative ion or anion. Charges are written as superscripts, as in Na⁺, Cl⁻ or ²⁻. Ionic compounds are built entirely from ions locked together by electrostatic attraction.
For example
When salt dissolves in your dal, the crystal breaks into free Na⁺ and Cl⁻ ions; that is why salt water conducts electricity while sugar water does not.