Concept:The boiling point is a direct measure of the thermal energy required to overcome intermolecular forces (IMFs) in a liquid.
Formula:$$ \text{Boiling Point} \propto \text{Intermolecular Forces} $$
Solution:- Water (\( \text{H}_2\text{O} \)) contains extensive, strong hydrogen bonds between its molecules.
- Petrol (a mixture of hydrocarbons like octane) is non-polar and relies exclusively on weak London dispersion forces.
- Because hydrogen bonds are significantly stronger than London dispersion forces, water requires much more heat energy to vaporize.
Why other options are incorrect:Stating the forces are "weaker" or "negligible" contradicts the high boiling point (\( 100^\circ\text{C} \)) of water compared to the highly volatile nature of petrol.
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