
Petrol is a strong solvent made of hydrocarbons. The rubber in a balloon is made of long, stretchy polymer chains (latex). When petrol touches the balloon, it starts dissolving or weakening these chains. The rubber loses its elasticity and strength very quickly. 👉 In simple words: Petrol “melts” the rubbery structure of the balloon. Once the rubber becomes weak, it can’t hold the air inside anymore, so the balloon pops instantly.