Предмет: Химия, автор: artomsolovej43

Рассчитайте массу воды, необходимой для получения жидкого 12% гидроксида калия из 720 г 36% жидкого гидроксида калия!
Даю 40 баллов!!!

Ответы

Автор ответа: unmime341
0

Сначала рассчитаем сколько воды мы в растворе на данный момент:

720*0.36=259.2 - масса KOH

720-259.2=460.8 - масса воды в первом растворе

Так как массовая доля раствора рассчитывается по формуле "масса вещества деленная на массу раствора", то масса раствора равна массе вещества деленного на массовую долю

Найдем массу 2 раствора:

259.2:0.12=2160- масса раствора, из которой 2160-259.2=1900.8- масса воды.

1900.8-460.8=1440

Ответ: 1440 грамм воды необходимо добавить

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