Предмет: Химия, автор: lerasolodilova1

К 260г 15% раствора, добавили 40г соли. Найти w полученного раствора

Ответы

Автор ответа: kolomycevan

Ответ:26%

Объяснение:

Дано:

m1(р-ра ) = 260г

ω(р-ра ) =15%

m2 (соли )=40г

Найти:

ω2(р-ра ) -?

Решение:

Mассовая доля растворенного вещества = Mассе растворенного вещества / Масса раствора *100%

ω = m р.в-ва/ m р-ра*100%

m р.в-ва=m р-ра*ω/100%

m р.в-ва=260*15/100=39г

m р.в-ва= 39г+40г=79г

m р-ра= m р.в-ва+ m растворителя(Н2О)

m р-ра=260г+40г=300г

ω = m р.в-ва/ m р-ра*100%

ω2(р-ра )=79г/300*100%=26%

Ответ: 26%

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