Wвсех элементов в соединениях: hpo3 ca(no3)2 fn3(po4)2

M(HPO3)=80
W(H)=(100*1)/80=1,25%
W(P)=(31*100)/80=38,75%
W(O)=(48*100)/80=60%
M(Ca(NO3)2)=164
W(Ca)=(40*100)/164=24,4%
W(N)=(28*100)/164=17,07%
W(O)=(96*100)/164=58,5%
M(Fe3(PO4)2)=168+62+128=358
W(Fe)=(168*100)/358=47%
W(P)=(62*100)/358=17,3%
W(O)=(128*100)/358=35,8%