Предмет: Химия, автор: vostroknutik

Вычислите массу Фторида кальция необходимого для приготовления 280г 36%-ного раствора фторида кальция

Ответы

Автор ответа: invincible17

Ответ:

100.8 грамм CaF2

Объяснение:

m(р-ра) = 280 грамм

w%(р-ра) = 36%

m(растворенного в-ва) = ?

$\frac{m1}{m1 + m2} \times 100\%$

$\frac{x}{280} = 0.36$

x=100.8 грамм CaF2

invincible17: спасибо!

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