Ответ:

Объяснение:

Mr(H3PO4) = 1*3 + 31 + 16*4 = 98

W(H) = Ar(H) *n / Mr(H3PO4)  *100% = 1*3 / 98  *100% = 3%

W(P) = Ar(P) *n / Mr(H3PO4)  *100% = 31*1 / 98  *100% = 32%

W(O) = Ar(O) *n / Mr(H3PO4)  *100% = 16*4 / 98  *100% =65%

Ответ:

Mr(H3PO4)=1×3+31+16×4=98

W(H)=3/98×100%=3%

W(P)=31/98×100%=31%

W(O)=64/98×100%=65%