Could you explain why water has a high latent heat of vapourisation?

A water molecule is polar. Due to the uneven sharing of electrons in the hydrogen-oxygen covalent bond, the oxygen molecule is slightly negatively charged and the hydrogen atoms are slightly positively charged. Due to this, intermolecular forces exist between water molecules, named hydrogen bonds. Hydrogen bonds require more energy to break than regular vander waals forces, therefore when heating a sample of water up, each hydrogen bond must be broken to vaporise the sample, which requires more energy, resulting in a higher heat of vaporisation, compared to other molecules of similar molecular mass.

SJ

Related Chemistry A Level answers

All answers ▸

Can you give and explain the mechanism for the reaction between aqueous Sodium Hydroxide (NaOH) and Chloroethane at room temperature? What is a competing reaction which may occur and how would you promote this reaction?


What does ‘aromatic’ mean?


Why does lithium have a higher melting point than sodium


Explain why the product of a nucleophilic addition to butanone does not effect plane polarized light.