Another simple question. When we take 1 litre of Liquid nitrogen and place it in a pressure vessel made of steel and seal this vessel, so that the vessel contains just Liquid Nitrogen. Does the vessel feel cold on the outside? Does the liquid Nitrogen remain at it's quantity even though the vessel is cold? A sealed vessel with Liquid Nitrogen in it remains static in form but is cold on the outside for how long? I know these are probably pretty simple questions but I ask that if the container remains fairly static in form ( liquid Nitrogen included) could it be said that the external temperature of the vessel is capable of work?