Объяснение:
Mr(NO2) = 14+16*2 =46
W(N) = Ar(N) *n / Mr(NO2) *100% = 14*1 / 46 *100% =30%
W(O) = Ar(O) *n / Mr(NO2) *100% = 16*2 / 46 *100% = 70%
Mr(Fe2O3) = 56*2 + 16*3 = 160
W(Fe) = Ar(Fe) *n / Mr(Fe2O3) *100% = 56*2 / 160 *100% =70%
W(O) = Ar(O) *n / Mr(Fe2O3) *100% = 16*3 / 160 *100% = 30%
