ELi5: How is liquid nitrogen super cold and in the form of liquid when the container itself is in a room temperature environment?
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> the container itself is in a room temperature environment?
Almost irrelevant. You can take a bottle of water out of the freezer and it won’t instantly melt when room temperature air meets the bottle, right?
Heat transfer takes time, and it takes more time if it needs to go through something that is not good at conducting heat. Even if the LN was just chilling in a bowl it would take time for it to boil away (a fairly short time, but it woudln’t be instant regardless). The non-pressurized dewars you see people pouring liquid nitrogen out of are specifically made to minimize heat transfer. They are double walled with a vacuum between the layers, the cork at the top is made of thermal insulating foam, etc. They cost a couple hundred dollar apiece, they aren’t your average water bottle.
The liquid still boils away, but at a massively slowed rate because it is almost completely cut off from the energy (the outside heat) it needs to boil into a gas.
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