Вопрос школьника по предмету Химия
В 120 г воды растворили 40 г поваренной соли. Какова массовая доля хлорида натрия в растворе?
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Ответ учителя по предмету Химия
Ответ:
дано:
m воды (H2O)-120гр
m соли (NaCl)-40гр
w-?
решение:
w=(m вещ-ва/ m раствора)* 100%
w=(40/(40+120)))*100%=0,25*100%=25%
ответ:25%
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