Вопрос школьника по предмету Химия
СРОЧНО: Магній масою 15 г, який містить 20% домішок, спалили у кисні. Яка маса магній оксиду утворилася?
Ответ учителя по предмету Химия
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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