Question

What is the limiting reagent?

Answer 1

The limiting reagent is `CO`..........

Explanation:

`Fe_2O_3(s) + 3CO(g) rarr 2Fe(s) + 3CO_2(g)`

And thus `"ferric oxide"` reacts with THREE equiv `CO` to give us 2 equiv iron metal, and 3 equiv of carbon dioxide.

`"Moles of ferric oxide"=(21.00*g)/(159.69*g*mol^-1)=0.132*mol`

`"Moles of carbon monoxide"=(10.50*g)/(28.01*g*mol^-1)=0.375*mol`

Given these molar quantities, ONLY `0.125*mol` `"ferric oxide"` will react, given that it is the reagent in excess, and carbon monoxide is the reagent is in deficiency.