Nitrogen Demos

For the whole chemistry period, we had liquid nitrogen demonstrations. I was so excited for this demo. If I remember correctly nitrogen boils at 77K and freezes at 63K. It's hard for me to imagine how cold it is, but it could probably damage our systems. The chemistry teachers froze stuff like flowers, bouncy balls, balloons, and rubber bands.  We even saw them put the liquid nitrogen under so much pressure that it turned into a solid!  As a joke they took someone's twenty dollar bill and froze it and gave back a one dollar bill because liquid nitrogen shrinks stuff. As a side demo, they lit frozen methane on fire (which I've only seen in videos). And finally, we made vanilla ice cream with the liquid nitrogen. The Chem teachers mixed together some ingredients and added liquid nitrogen to freeze it and add bubbles. It tasted "legit". The whole demonstration was so cool!