Question

Account for the following :

1. PH₃ has lower boiling point than NH₃.

2. Pentahalides are more covalent than trihalides.

3. ICI is more reactive than I₂.

Answer 1

1. NH₃, PH₃ molecules are not associated through intermolecular hydrogen bonding in liquid state.

2. Higher the positive oxidation state of central atom, more will be its polarising power which, in turn, increases the covalent character.

3. Bond energy of I-CI bond is less than that fo I-I bond.