The number of white coloured salts among the following is ..........

The colour of the salts are as follows,

${SrSO}_{4}$- white
$Mg\left({NH}_{4}\right){PO}_{4}$ - white
${BaCrO}_{4}$ - yellow
$Mn ( OH{)}_{2}$ - white
${PbSO}_{4}$ - white
${PbCrO}_{4}$ - yellow
$AgBr$ - pale yellow
${PbI}_{2}$ - yellow
${CaC}_{2}{O}_{4}$ - white

\left[Fe ( OH{)}_{2}\left({CH}_{3}COO\right)\right] – Brown Red

Hence the number of salts which are white in colour is $5$.