Of two oxides of iron, the first contained 22% and the second contained 30% of oxygen by weight. The ratio of weights of iron in the two oxides that combine with the same weight of oxygen is (J&K CET 2008)

Let, the weight of two oxides = 100 g Case-1: Percentage of oxygen = 22% Weight of oxygen = 22 100 22 100 g g x Weight of iron = 100 22 78g Weight of iron 78 Weight of oxygen 22 ------- (1) Case 2: The percentage of oxygen = 30% Weight of oxygen = 30 100 30 100 g g x MOLE & EQUIVALENT CONCEPT 52 Weight of iron =100 30 70g Weight of iron 70 Weight of oxygen 30 ------(2) Therefore, the ratio of iron in the two oxides that combine with the same weight of oxygen is 78 3.545454545 22 1.52 70 2.333333333 30 Hence, the ratio is 3:2