Q12 / 90 · JEE Main 2013 (07 Apr) · Chemistry
Experimentally it was found that a metal oxide has formula . Metal M, is present as and in its oxide. Fraction of the metal which exists as would be:
- A
- B
- C
- Correct answerD
Solution
Consider one mole of the oxide, then
Moles of M = 0.98; Moles of O2- = 1
Let 'x' moles of M are in +3 oxidation state, then Moles of M2+ = 0.98-x
On doing charge balancing we get
(0.98 - x)2 + 3x = 2
Or 1.96 - 2x + 3x - 2 = 0
Or x = 0.04
Moles of M = 0.98; Moles of O2- = 1
Let 'x' moles of M are in +3 oxidation state, then Moles of M2+ = 0.98-x
On doing charge balancing we get
(0.98 - x)2 + 3x = 2
Or 1.96 - 2x + 3x - 2 = 0
Or x = 0.04
Hence, the correct answer is option: 'D'.