Предмет: Химия, автор: adik61

1)Смешали 300 грамм воды и 50 грамм хлорида магния. Определить массовую долю соли в полученном растворе.
2)Рассчитать количество вещества меди, необходимо для получения 4 моль оксида меди(II). Какая масса кислорода потребуется для реакции?
Решите оба! Заранее спасибо

Ответы

Автор ответа: n2324
0
     50гр   300гр    хгр
  1) MgCl2+H2O=2HCl+MgO
   94гр    18гр     72гр
тут нужно разделить меньше будем рещать
50/94=0,5
300/18=16,6
  тут меньше -МgCl2
x=50*72/94
x=38.2гр  НСl
  хм     хг        4м
2)2Сu+O2=2CuO
 2м     32гр        2
х=2*4/2
х=4  мольСu
x=32*4/2
x=64 гр  О2


adik61: а другой тот кто помог 1 решил по другому чьё переписывать
adik61: ???
Автор ответа: DJToxa
1
2.Ответ: n(Cu)=4моль; m(O2)=64г
Приложения:

DJToxa: мое)
adik61: ок
adik61: ;)
adik61: можно 1 вопрос
DJToxa: да
adik61: почему во 2 задаче n(Cu)=n(CuO)=4 моль
DJToxa: потому что перед ними стоят одинаковые коэффициенты(двойки),поэтому и равное хим количество
adik61: разве есть такое правило?
adik61: ответь
DJToxa: да
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