2 holes are punctured at a slanting/glacing angle into a ping pong ball. It is then immersed in liquid nitrogen. The air inside it cools. This lowers the air pressure inside the ping pong ball. Liquid nitrogen then partly fills the ping pong ball. The ping pong ball will start to spin as cold liquid nitrogen boils shooting out cold nitrogen gas from these 2 holes.
Anything that has air will expand in a vacuum. When air is evacuated(exhausted out of)from a chamber, 2 mashmallows are seen to expand, as they contain some air inside them. More videos can be seen on PL Education Centre(Singapore) website: http://www.plenrich. com
A helium-filled balloon is less dense than air and it can float upwards. When the balloon is shrunk by pouring liquid nitrogen over it, it becomes denser than air and falls to the ground.
Upon warming and expanding, it will fly up again.This video is produced in Singapore. More videos on www.plenrich.com
When liquid nitrogen cooled a piece of biscuit to about -196 degree Celsius, and when we eat (munch) it with our mouth closed, streams of condensed water vapour will come out from the nostrils
Just like a balloon filled with air sinks in air, a balloon filled with helium will not rise, but sink in a helium surrounding.Kindly look into http://www.plsingapo re.com for more science videos and info
Very cold liquid nitrogen vapourises immediately upon contact with warm object s like our skin. The vapour forms an insulating layer preventing more heat being lost from our warm palms. Caution: do not did your hand into liquid nitrogen for more than 1 second. Do visit our education website at www.PLsingapore.com
Liquid nitrogen boils at -196 degree Celsius. When the liquid boils out of a whistling kettle, it makes the latter whistle, but the kettle is cold and not hot as common perception of a whistling kettle whistling is associated with boiling hot water.
Very cold liquid nitrogen slows down the air molecules inside a balloon and its volume shrinks. The flexible nature of the macromolecules of rubber also changes to be stiff.
These pressure cups can support up to 60 kg force. They are usually used in carrying huge piece of glass. It demonstrates the great pressure exerted by our atmospheric pressure at sea level
One is never too young to learn about Science and liquid nitrogen. Here Isabel makes a lolly with her grandpa :) Visit www.PLsingapore.com for more free Science vids.
![Liquid nitrogen poured onto students\](http://img.youtube.com/vi/zJwOTFm6DWg/2.jpg "Liquid nitrogen poured onto students\")
