SuSO.

SO2

P2O5.

H2SO4

CaCO3

Fe (OH) 3.

Найти относительную молекулярную массу.

Mr (So2) = Ar (S) + Ar (O) * 2=32+16*2=64

Mr (P2O5) Ar (P) * 2+Ar (O) * 5=31*2+16*5=62+80=142

Mr (H2SO4) = Ar (H) * 2+Ar (S) + Ar (O) * 4=2+32+64=98

Mr (CaCO3) = Ar (Ca) + Ar (C) + Ar (O) * 3=40+12+48=100

Mr (Fe (OH) 3) = Ar (Fe) + Ar (O) * 3+Ar (H) * 3=56+3+48=107

SO2 Mr=32+16*2=64; P2O5 Mr=31*2+16*5=142; H2SO4 Mr=1*2+32+16*4=98; CaCO3 Mr=40+12+16*3=100; Fe (OH) 3 Mr=56+16*3+1*3=107