What energy is in petrol?

The primary type of energy contained in petrol is chemical energy. Petrol, also known as gasoline, is a mixture of hydrocarbons, mainly consisting of octanes, heptanes, and other related compounds. When petrol is burned, the chemical energy stored within its molecular bonds is released in the form of heat and light energy. This exothermic reaction (or combustion) causes the expansion of gases, which generates significant pressure and heat, making it useful as a fuel for internal combustion engines commonly used in vehicles. The chemical energy in petrol is also responsible for its high calorific value, which represents the amount of heat energy released when a specific amount of fuel is completely combusted.