Question

The equivalent mass of a trivalent metal element is 9 g eq^-1 the molar mass of its anhydrous oxide is

Options

• 102 g

• 27 g

• 270 g

• 78 g

Answer 1

102 g

Explanation:

Let the trivalent metal be M³⁺

Equivalent mass = `"mass of the metal"/"valance factor"`

9 g eq^-1 = `"mass of the metal"/ "3 eq"`

Mass of the metal = 27 g

Oxide formed M₂O₃;

Mass of the oxide = (2 × 27) + (3 × 16)

= 102 g