Question

In a metal deficient oxide sample, \(M_xY_2O_4\) (M and Y are metals), \(M\) is present in both +2 and +3 oxidation states and Y is in +3 oxidation state. If the fraction of \(M^{2+}\) ions present in \(M\) is \(\frac13\), the value of \(X\) is _____.

(A) 0.25

(B) 0.33

(C) 0.67

(D) 0.75

Answer 1

Correct option is (D) 0.75

\(M_xY_2O_4\)

\(M^{+2} = \frac X3, M^{+3} = \frac{2X}3\)

So, total of O.N. of all atoms

\(\frac{2X}3 + 3\left(\frac{2X}3\right) + 2(+3) + 4(-2) = 0\)

\(\frac{2X}3 + 2X + 6 - 8 = 0\)

\(\frac{8X}3 = 2\)

\(X = \frac 68 = \frac34 = 0.75\)