Требуется приготовить 15%-ный раствор едкого кали. Массы используемых 12%-ного и 20%-ного растворов относятся как __ : 1.

Требуется приготовить 15%-ный раствор едкого кали. Массы используемых 12%-ного и 20%-ного растворов относятся как __ : 1.
- Предмет:
  Химия
- Автор:
  noe
- 6 лет назад

Ответы 1

0,12                   0,05

             0,15                      - конверт Пирсона.

0,2                      0,03

пусть масса 12%-ного р-ра равна "х" г , масса 20%-ного р-ра "у" г, тогда

m(р-ра 12%) =(x*0,05) : 0,08;

m(р-ра) 20% =( y*0,03) :0,08;

         x:y =3:5

.............................................................................................................................................................
- Автор:
  riyabolton
- 6 лет назад
- 0
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Требуется приготовить 15%-ный раствор едкого кали. Массы используемых 12%-ного и 20%-ного растворов относятся как __ : 1.

Ответы 1

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