Предмет: Химия, автор: aza1997

Сколько граммов Na2CO3 и воды требуется для приготовления 1 кг 10% раствора ?

Ответы

Автор ответа: Бизубик

Из формулы для расчёта концентрации Cм=n/V находим количество вещества: n(Na2CO3) = Cм*V = 0,1 моль/л*250 л = 25 моль Далее - массу вещества: m(Na2CO3)=n*M=25 моль*106 г/моль =2650 г

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