Verified answer

Ответ:

Объяснение:

Mr(CaCO3) = 40 + 12 + 16*3 = 100

W(O) = Ar(O) *n / Mr(CaCO3)  *100% = 16*3 / 100  *100% = 48%

Mr(Na2O) = 23*2 + 16 = 62 г/моль

W(O) = Ar(O) *n / Mr(Na2O)  *100% = 16*1 / 62  *100% =26%

Mr(HNO3) = 1+14 + 16*3 = 63

W(O) = Ar(O) *n / Mr(HNO3)   *100% = 16*3 / 63  *100% =76%