Chemical Bonding and Molecular Structure — Chemistry STD 11 Science — Question

A hydrogen bond is defined as an attractive force acting between the hydrogen attached to an electronegative atom of one molecule and an electronegative atom of a different molecule (may be of the same kind).

Due to a difference between electronegativities, the bond pair between hydrogen and the electronegative atom gets drifted far away from the hydrogen atom. As a result, a hydrogen atom becomes electropositive with respect to the other atom and acquires a positive charge. a positive charge.

$4^\delta-\text{X}^{\delta-}.......\text{H}^{\delta+}-\text{X}^{\delta-}.......\text{H}^{\delta+}-\text{X}^\delta$

The magnitude of H-bonding is maximum in the solid state and minimum in the gaseous state.

There are two types of H-bonds:

1. Intermolecular H-bond e.g., HF, H₂O etc.
2. Intramolecular H-bond e.g., o-nitrophenol.

3. Hydrogen bonds are stronger than Van der Walls forces since hydrogen bonds are regarded as an extreme form of dipole-dipole interaction.