01.04.2022

Масса воды в (г) которую необходимо добавить к 140 г 40% раствора кислоты для получения 15% раствора=?

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Масса воды в (г) которую необходимо добавить к 140 г 40% раствора кислоты для получения 15% раствора=?

Ответ учителя по предмету Химия

х+140*0,4=140*0,15

х+56=21

х=35

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