Question

The composition of a sample of wustite is Fe_0.93O_1.0· The iron is present in the form of Fe(III) is ______%.

Options

• 20.63

• 15.05

• 09.10

• 13.08

Answer 1

The composition of a sample of wustite is Fe_0.93O_1.0· The iron is present in the form of Fe(III) is 15.05 %.

Explanation:

\[\ce{3Fe^{2+} -> 2Fe^{3+}}\]

\[\ce{N_A -> 0.93 N_A}\] mix of Fe²⁺ and Fe³⁺ of Fe²⁺

\[\ce{2(N_A - 0.093 N_A) -> Fe^{3+}}\]

(0.07 N_A)2 = 0.14 N_A

N_A - 3(0.07)N_A = 0.79 N_A

Percentage of Fe(III) = `(0.14 " N"_"A")/(0.93 " N"_"A") xx 100`

Percentage of Fe(III) = 15.05%