Question

Calculate the mass of iron which will be converted into its oxide by the action of $18g$ of steam on it:

• A. $37.3g$
• B. $3.73g$
• C. $56g$
• D. $5.6g$

Answer 1

The correct option is A $37.3g$

The corresponding balanced chemical reaction is,
$2Fe+3H_2{O}_{\left(g\right)}\to F{e}_2{O}_3+3H_2$
$3\text{moles of}{H}_2{O}_{\left(g\right)}\text{converts}2\text{moles of Fe to its oxides}$
Given ,
$18g$ of $H_2{O}_{\left(g\right)}$
So moles of $H_2{O}_{\left(g\right)}=\frac{18}{18}=1$
Then,
$1\text{moles of}{H}_2{O}_{\left(g\right)}\text{converts}\frac{2}{3}\text{moles of Fe to its oxides}$
Mass of $Fe=\frac{2\times 56}{3}=37.33g$