Предмет: Химия, автор: annakrechko04

Очень срочно!!! Ребята прошу помогите!!! При действии на смесь магния и бария избытка серной кислоты выделилось 2,4 г бесцветного газа. Если эту же смесь поместить в избыток воды, то выделяется только 0,40 г того же газа. Вычислите массу исходной смесси металлов.

Ответы

Автор ответа: ДРАКУла5611
3
1. Mg+H2SO4=MgSO4+H2
M(H2)=2 г/моль
n(H2)=1,2 моль

2. Ba+H2SO4=BaSO4+H2
n(H2)=1,2 моль

3. Mg+H2O=MgO+H2
n(H2)=0,4/2=0,2 моль

4. Ba+H2O=BaO+H2
n(H2)=0,4/2=0,2 моль

5.n(H2)-n(H2)=1,2-0,2=1 моль

Ar(Mg)=24 г/моль
Ar(Ba)=137 г/моль

m(Mg)=1×24=24 г
m(Ba)=1×137=137 г
24+137=161 г - масса смеси
Ответ: 161 г масса смеси

annakrechko04: Огромное спасибо!!!
ДРАКУла5611: не за что
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