Verified answer

Ответ:

Объяснение:

Mr(H2O) = 1*2 + 16 = 18

W(O) = Ar(O) *n / Mr(H2O)  *100% = 16*1 / 18  *100% =89%

Mr(H2SO4) = 1*2 + 32 + 16*4 = 98

W(O) = Ar(O) *n / Mr(H2SO4)  *100% = 16*4 / 98  *100% =65%