If two atoms differ considerably in their electronegativity - as sodium and chloride do - then one of the atoms will lose its electron to the other atom.

To balance PbO2 = PbO + O2 you'll need to be sure to count all of atoms on each side of the chemical equation. The covalent bonds could occur in a polyatomic ion in either the cation or the anion.

A molecule or compound is made when two or more atoms form a chemical bond, linking them together. setTimeout(