Предмет: Химия, автор: avramkinayana

СРОЧНО: Магній масою 15 г, який містить 20% домішок, спалили у кисні. Яка маса магній оксиду утворилася?

Ответы

Автор ответа: Potassium
1

20% от 15 г = 3 г

15 - 3 = 12 г — масса магния без примесей.

2Mg + O2 = 2MgO

12/48 = x/80

x = (12*80)/48 = 20 грамм

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