# What formula represents strontium phosphate?

Mar 17, 2016

$S {r}_{3} {\left(P {O}_{4}\right)}_{2}$

#### Explanation:

The metal ion Strontium has an ionic charge of +2,

The polyatomic ion Phosphate has an ionic charge of -3, $P {O}_{4}^{-} 3$

In order for the ionic molecule strontium phosphate to form a bond the charges need to be equal and opposite.

Therefore, we will need 3 strontium ions

$S {r}^{+} 2$
$S {r}^{+} 2$
$S {r}^{+} 2$

for a total ionic charge of +6
to bond with 2 phosphate ions

$P {O}_{4}^{-} 3$
$P {O}_{4}^{-} 3$

for a total ionic charge of -6

to form the molecule

$S {r}_{3} {\left(P {O}_{4}\right)}_{2}$