Answer
$ Percentage of Ca = 38.71$
$Percentage of P = 20.00 $
$ Percentage of O = 41.29$
Work Step by Step
Molecular mass of $Ca_{3}(PO_{4})_{2} = 3 \times 40+2 \times 31+8 \times 16$
= 310 g
Total weight of Ca in 310 g sample =$3 \times 40$ = 120 g
Total weight of P in 310 g sample =$2 \times 31$ = 62 g
Total weight of O in 310 g sample =$8 \times 16$ = 128 g
Therfore,
Percentage of Ca =$(120\times100)\div310 = 38.71$
Percentage of P =$(62\times100)\div310 = 20.00 $
Percentage of O = $(128\times100)\div310 =41.29$
