JEE Main 2026 · 6 Apr · Shift 1 · Chemistry Q51

ChemistrySingle correct+4 / -1Question 51 of 75

An oxide of iron contains 69.9% iron, its empirical formula, is:

(Given : Molar mass of Fe and O are 56 and 16 g mol $^{-1}$ respectively.)

FeO

\ce{Fe2O3}

\ce{Fe3O4}

\ce{FeO3}

Answer and worked solution

Official answer: B

Mole ratio.

So Fe : O = 1 : 1.5 = 2 : 3.

Formula: $\ce{Fe2O3}$ .

(B)

Topics:Empirical and molecular formula

JEE Main 2026 · 6 Apr · Shift 1, Chemistry question 51