Iron can be obtained by reaction of iron oxide `(Fe_3O_4)` with CO according to the reaction :
`Fe_3O_4 +4CO to 3Fe + 4CO_2`
How many kg of `Fe_3O_4` should be heated with CO to get 3 kg of iron?

Options

A. `6.92 `kg
B. `8.12` kg
C. `20.8` kg
D. `24.4 ` kg

Answer

B

Explanation

1 mole `Fe_(3)O_(4) (232 g) = 3 " mole " Fe (168 g) `
Mmount of `Fe_(3)O_(4)` required for 5 kg iron ` = (232)/(168) xx 5 ` kg
` = 6.904 ` kg
Since, efficiency of the reaction is 85% , hence, the actual required amount of `Fe_(3)O_(4)` will
be ` = (100 xx 6.904)/85 kg , i.e. = 8.12 ` kg .