Why do aerosol and deodorant cans warn 'do not heat or incinerate'?
At fixed volume, a gas's pressure rises in direct proportion to its absolute temperature (Gay-Lussac's law, P ∝ T).
At fixed volume, a gas's pressure rises in direct proportion to its absolute temperature (Gay-Lussac's law, P ∝ T). A sealed can can't expand, so heating it drives the internal pressure up until the can ruptures — an explosion. That's why you keep pressurised cans away from fire and hot cars.
Key point
At constant volume, P ∝ T (Gay-Lussac) — heating a sealed can spikes the pressure until it bursts.
Common mistake
thinking a rigid can is safe because its volume can't change.
Memory tip
can't expand → heating just raises the pressure → bang.
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