# What is the formula of aluminum phosphate?

Nov 2, 2016

The formula unit for aluminum phosphate is $\text{AlPO"_4}$.
The formula for the aluminum cation is $\text{Al"^(3+)}$, and the formula for the phosphate anion is $\text{PO"_4""^(3-)}$. So the formula unit for aluminum phosphate represents a $1 : 1$ ratio of aluminum and phosphate ions, which is represented as $\text{AlPO"_4}$.