Why dose frost form on butane gas cylinders when they are being used?

Answer 1

In expanding from its liquid form to its gaseous form work is done. The energy for this work is taken from the air surrounding the cylinder, causing the air temperature to drop, causing condensation and then freezing of the moisture in the air.
The energy required for the liquid/gas transition is known as the Latent Heat of Vaporisation.

Answer 2

Butane gas is held, under pressure, inside the cylinder at around -44 deg Fahrenheit. When it is released from the cylinder it starts to "boil" a bit like water.

Unlike water, that needs an external heat source, like the gas ring on a cooker, butane produces its own heat source as part of its chemical reaction to the outside, ambient temperature.

This is where the frost comes from. So instead of producing steam, like water does, the butane's steam is the frost bit...now, I'm going back a LONG way to my physics lesson at school so I hope I got this one right!!!

Answer 3

Because the butane liquid becomes a gas and absorbs energy. Do you mean propane gas cylinder? The same is true for propane.

Answer 4

The reason is that butane is compressed to form a liquid in your lighter. When you release it it rushes out and EXPANDS to form a gas:

C4H10(l) --> C4H10(g)

Due to this expansion the cooling effect can be as much as -20 degree C (ref : http://en.wikipedia.org/wiki/Butane)

Answer 5

V. simplistic explanation... If the gas is suddenly released, work has to be done. If there is no time for energy to come from its surroundings, this work comes at the expenditure of energy from the internal energy of the gas. ie it cools

Answer 6

Because it is stored at a low temperature.