# What is the ionic compound formula of ammonium sulfate?

Ammonium Sulfate is an ionic compound formed by two polyatomic ions, Ammonium $N {H}_{4}^{+}$ and Sulfate $S {O}_{4}^{-}$.
In order for these two polyatomic ions to bond the charges must be equal and opposite. Therefore, it will take two +1 ammonium ions to balance the one -2 sulfate ion. This will make the formula for Ammonium Sulfate ${\left(N {H}_{4}\right)}_{2} S {O}_{4}$.