Thread: Gases?

When compressed gas (eg CO2) is released it feels "cold". Is this because the gas is absorbing thermal energy from the environment as it expands?
If the gas particles were releasing energy the gas should be "hot".

compressed gasses fees cold on release, because:

in order for it to fit in the cansiter, and be pusehd out by a propellant, it must be compressed, turning it to a liquid/solid
so when it is released, the heat energy in the environment is transferred to this liquid/solid so that it can retake its natural form as a gas. and if it is taknig heat from that environment(eg. your hand) then it feels cold, because the heat has left the environment.

that is the principles used in refridgeration

Yeah you're right

In order to expand the liquid need MORE kinetic energy to become a gas.

So it changes his thermal into kinectic energy, it uses energy so it gets colder.

Funny thing I've seen it happen in real live. When I was camping and because of my clumsiness I released an newly opened butane gas bottle. It started to expand enormously, afterwards the exterioir site showed little frosen water druplets