Question

Hydrogen bonding is responsible for:

• A. Higher boiling point of water in comparison to $H_{2}S$
• B. Double stranded structure of DNA
• C. Lower density of solid ice at $0{}^{\circ }\text{C}$ in comparison to water
• D. All of the above

Answer 1

The correct option is D All of the above

(a) The boiling points of compounds depends on the intermolecular forces. In $H_{2}O$ intermolecular $H-$ bonding is present but in case of $H_{2}S$ only dipole-dipole interaction is present. Since, $H-$ bonding is stronger than the dipole-dipole interactions, hence $H_{2}O$ has higher boiling point than $H_{2}S$.

(b) Hydrogen bonding holds two strands together in DNA.

(c) Ice is less denser than water because in ice the molecules arrange themselves in a rigid tetrahedral structure through hydrogen bond. Due to which cage like spaces remain in ice. Since, the volume of ice increases, hence it is less denser.