Question

Which of the following statements are FALSE about lanthanoids?

(I) They have lower heat of atomization than transition metals

(II) They are soft metals with silvery white colour and densities of about 7 g cm⁻³.

(III) They react with water to give the metal hydroxide and oxygen gas.

(IV) They form hydroxides, which are covalent and basic.

Options

• (I) and (II)

• (II) and (III)

• (I) and (IV)

• (III) and (IV)

Answer 1

(III) and (IV)

Explanation:

When lanthanoids come into contact with water, they produce metal hydroxide and hydrogen gas. Ionic and basic hydroxides make up their hydroxides.