Предмет: Химия, автор: YASATANA

Растворимость карбоната натрия при 20о C составляет 21,8 г в 100 г воды, а при 40о C - 48,8 г. Вычислите массу кристаллической соды, которая выпадет в осадок, если 200 г насыщенного при 40о C раствора охладить до 20о C.

Ответы

Автор ответа: nikitokkk

m(Na2CO3)=200/100*48.8=97.6 г
m(Na2CO3)20'=200/100*21.8=43.6 г
m(Na2CO3)↓=97.6/43.6=54 г

Автор ответа: YASATANA

Правильный ответ 157,9 гр

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