Question

Мr (H3PO4) = Мr (SO2) =
Мr (FeCl2) =
СРОЧНО ОЧЕНЬ СРОЧНО

Answer 1

Mr(H3PO4)= Ar(H)*n(H)+Ar(P)*n(P)+Ar(O)*n(O)=1*3+31*1+16*4=3+31+64=98

Mr(SO2)=32+16*2=64

Mr[FeCl2] = Ar[Fe] + Ar[Cl] * 2 = 55.845 + 35.453 * 2 = 126.