Предмет: Химия, автор: fox852

К 550 граммам 48%-ного раствора ортофосфорной кислоты добавили 200 граммов воды. Рассчитай массовую долю растворённого вещества в образовавшемся растворе. Ответ следует округлить до десятых. Ответ: %.

Ответы

Автор ответа: nanem1975

Ответ:

m1(pаствор)= 550г.

m(растворенное вещество)=550×48÷100=264г

m2(pаствор)= 550г+200г.=750г.

W=m(растворенное вещество)÷m(pаствор)×100%

W=264÷750×100%

W(массовую дол.)=35.2%

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