Предмет: Химия, автор: medixxx1

В какой массе воды следует растворить 11,7г NaCl, чтобы получить раствор NaCl с массовой долей 7,5%​

Ответы

Автор ответа: Bretzel723
1
W(NaCl)= m(NaCl):mраствора • 100%
mраствора=m(NaCl):W(NaCl)
W(NaCl)=7,5%= 0,075
mраствора=11,7:0,075= 156г

mраствора=m(NaCl) + m(H2O)
m(H2O)= mраствора - m(NaCl)
m(H2O)=156-11,7=144,3г

Ответ:144,3г
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