When the balloon is removed from the liquid nitrogen then air inside the balloon begins to get warm again and it expands. If you look closely, you can see that the air inside the balloon has turned into a liquid. (Water is a notable exception and ice floats!) As the air inside the balloon contracts, the balloon shrinks. Normally, when things get cold then contract, or get smaller. When a balloon is put into the liquid nitrogen the air inside gets cold. This is what causes the cloud when liquid nitrogen is poured into a beaker. Also, anything at normal room temperature is so much hotter than liquid nitrogen that the liquid nitrogen boils when it touches something. It’s so cold that it freezes anything it touches almost instantly. Liquid nitrogen is just very cold nitrogen. When a gas is made very cold, it turns into a liquid similar to water. Air is also made up of oxygen, carbon dioxide, hydrogen, water vapor, and many other gases in small amounts.
Eventually, the liquid nitrogen builds up enough energy in the cannon to shoot a cork across the room.Īs the liquid nitrogen heats up and boils, the pressure in the cannon increases until it blows off the cork. Liquid nitrogen is placed in a brass cannon with a cork on top to hold in the nitrogen molecules.
