Question

If a piece of iron gains 10% of its weight due to partial rusting into Fe2O3 the percentage of total iron that has rusted is :

• A. 23
• B. 13
• C. 23.3
• D. 25.67

Answer 1

Answer: (C)

23.3

Answer 2

(3)

Let wt. of Fe = 100 g so wt. of O2 = 10 g

2Fe +$\frac{3}{2}$O2 $\longrightarrow$ Fe2O3

by the stoichiometry of the reaction $\frac{10}{32}$ mole of O2 will combine with $\frac{10}{24}$mole of Fe