Uploaded by admin on January 30, 2016 at 9:25 am
Interesting Biology Project. Funny and Exciting project for all grade levels.
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The way she says water is so weird lol, woeder
Lol nice try, this is nowhere close to being a biological experiment. The word you are looking for is physics. This is a classic demonstration of how temperature affects pressure. In this case, the flame of the candles heats the gas inside the cup very quickly (it would have been better to use fewer candles; I will explain why in a moment) until most of the O2 inside the cup is converted to the less-flammable CO2. At this point, the flame is extinguished and the gas inside the cup begins to cool very quickly. When the gas is first heated, if less candles were used the flame would be smaller and would heat the gas inside the cup at a slower rate, and an observer would be able to see some gas escape the cup at its lip, forming bubbles briefly. The bubbles would stop coming out of the cup when the flame is extinguished. At that point, the air inside the cup would cool and the pressure inside the cup would drop to less than atmospheric pressure. This would allow the atmospheric pressure to push in the water from outside the edge of the cup. Now a word about the relation between temperature and pressure: when a gas is heated, its molecules become more excited. This means they fly around at faster speeds, and because each molecule has a mass and a velocity, it has a momentum. The molecules smack against the sides of their container harder and harder as they are heated. In this case, the gas inside the cup cannot move the cup's walls, but it can push the water at the lip of the cup out of the cup, which eventually ends up pushing some of the gas out of the cup, creating those bubbles I mentioned. THERE IS NO CHANGE IN AMOUNT OF GAS IN THE CUP AFTER THE CANDLE IS EXTINGUISHED, as mass can neither be created nor destroyed. What happens is the gas starts to cool down, and its molecules become less excited, so less speed, less momentum, and less pressure within the cup. Once the pressure inside the cup is sufficiently low enough for Earth's atmospheric pressure (14.7 psi) to push the water back into the cup, it does, and the cup begins to fill with water until the outside pressure is equalized with the internal pressure and gravitational force on the water trying to get it to the same level as the water outside the cup (in the bowl). Bottom line, this is a physics experiment and there is no vacuum created. And your shirt says you're from Harvard? xD nice.
This isn't a biology experiment …
I have an experiment proposal due tomorrow for my bio class and I am going to do that
thank u soooo much….
this is actually a chemistry experiment
This is really Truely AWESOME !!!!!!!
This isn't a biology experiment…
nice job getting into harvard.
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