Consider the following reaction : \[3 PbCl _2+2\left( NH _4\right)_3 PO _4 \rightarrow Pb _3\left( PO _4\right)_2+6 NH _…

Consider the following reaction :
\[3 PbCl _2+2\left( NH _4\right)_3 PO _4 \rightarrow Pb _3\left( PO _4\right)_2+6 NH _4 Cl\]

If \(72 mmol\) of \(PbCl _2\) is mixed with \(50 mmol\) of \(\left( NH _4\right)_3 PO _4\), then the amount of \(Pb _3\left( PO _4\right)_2\) formed is ________mmol (nearest integer).