Предмет: Химия, автор: NekoNyasha

Найти массу чистого железа, полученного при восстановлении руды (оксида железа трехвалентного)массой 345 гр водородом. Массовая доля оксида железа в руде 98%

Ответы

Автор ответа: SyncDima

m(Fe2O3)=345г
w(Fe2O3)=98%
m(Fe)=?
m(Fe2O3)=345*0.98=338.1г
M(Fe2O3)=159.6г/моль
n(Fe2O3)=338.1г/159.6г/моль=2.1моль
Fe2O3+3H2-->2Fe+3H2O
n(Fe)=2.1моль*2=4.2моль
m(Fe)=4.2моль*55.8г/моль=234.4 г

Автор ответа: NekoNyasha

Честное слово, вы меня спасли

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