Some ions are listed below: positive ions $\text{Ti}^{4+}$, $\text{Al}^{3+}$, $\text{Mg}^{2+}$, $\text{K}^+$ and negative ions $\text{PO}_4^{3-}$, $\text{SO}_4^{2-}$, $\text{NO}_3^-$, $\text{Cl}^-$. Which one of the formulae is incorrect?
- A$\text{Al}_3(\text{SO}_4)_2$
- B$\text{K}_3\text{PO}_4$
- C$\text{Mg(NO}_3)_2$
- D$\text{TiCl}_4$