Предмет: Химия, автор: valeriaslepcova21

Помогите, пожалуйста, с химией (8 класс)
Сколько миллилитров воды надо прилить к 150 г 3 % раствора, чтобы получить 4 % раствор?
Даю 40 б.

Ответы

Автор ответа: staskom70
1

Ответ:

m в-ва (NaOH)=150*0.3=45 г

w(в-ва)=  m(в-ва)/m(р-ра)

значит

0,04=45

       х+150

45=0.04*(х+150)

45=0.04х+6

39=0.04х

х=975

m(h2o)=975

Объяснение:

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