Предмет: Химия, автор: Kriiiistina99

вычислите массовую долю водорода: а) в воде б) в метане CH4

Ответы

Автор ответа: хихимик

w(H) в H2O = 2/18 =0,1111 или 11,11%

w(H) в CH4 = 4/16 =0,25 или 25%

Автор ответа: Zero3

а) берем массу интересуещего элемента (Н2) и дели на массу всего вещества (Н2О). Тогда (2*1/2*1+16) * 100% = 11%

б) Точно так же >> (4*1/4*1 + 12) * 100% = 25%

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