There are chemicals called “aerosol” that are a liquid when contained in pressure. When you release the pressure they expand into a gas and accelerate out of the can, pushing the other contents out with them. If you flip a can upside down and spray it you may see frost forming on a surface you aim it at, or you'll feel a can get cold the longer you spray cause it's the exact same mechanic that allows your air conditioning to work. This is compared to using compressed air which would need a much sturdier container, it's why the walls of air compressors are so thick
Meechgalhuquot t1_j9ke554 wrote
Reply to Eli5: how do pressurized spray cans work? Spray paint, cooking oils, hairspray etc by garlicknotter
There are chemicals called “aerosol” that are a liquid when contained in pressure. When you release the pressure they expand into a gas and accelerate out of the can, pushing the other contents out with them. If you flip a can upside down and spray it you may see frost forming on a surface you aim it at, or you'll feel a can get cold the longer you spray cause it's the exact same mechanic that allows your air conditioning to work. This is compared to using compressed air which would need a much sturdier container, it's why the walls of air compressors are so thick