Предмет: Химия, автор: 0000168

определите массовую долю кислорода в карбонате калия

Ответы

Автор ответа: Lirra

Дано:
K2CO3
Найти: W(O)-?
W= Ar*n/Mr
Mr(K2CO3)=39*2+12+16*3=138
W(O)= 16*3/138=48/138= 0,35.
Если в процентах, то 0,35*100%=35%
Ответ: W(O)=0,35

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