Freeze Water by Boiling

Water is placed in a bell jar and the vacuum pump is turned in. Eventually the water freezes. Watch and listen to find out why.

Category:

Howto & Style

Tags:

• Water
• change
• of
• state
• vacuum
• pump
• freeze

[rudmop]

@Diogenes2077 From the standpoint of thermodynamics the system is sealed from the environment by the bell jar. Molecules in the system are not all moving with the same kinetic energy; although the measurement of the average kinetic energy of all them together is the temperature. When a surface molecule is moving in a direction that it can escape the cup but still lacks the energy, it will be able to escape if another molecule with more kinetic energy has an elastic collision with it.

[missyrawien]

By saying that there is a difference in the molecules temperature to such a degree that they're left behind in solid form isn't he really saying his sample isn't pure water...?

If what he's showing is true, his physics is bollocs. I think this is a bit of a trick tbh...

[rudmop]

You need to know how hydrogen bonding in water and how temperature and pressure of water causes water to change its state. The solid molecules are not left behind, the cold ones are; they also are close enough together and moving slowly enough to set up strong intermolecular attractions via hydrogen bonding and establish a crystalline network.

[jman4622]

who gives a shit about ur arguements? its a cool video

[benjya999]

Correct - but it's because at high altitudes (ie low air pressure), water boils at a lower temperature. At the top of Mt Everest, water boils at about 69C, much cooler than the 100C at sea level.

[tonkapoplol]

where you can buy a vaccum like this

[iceowls]

Hi, thank you for the video.

I am interested in purchasing a vacuum pump to make ice from liquid water.

Where can I purchase them? How strong are they?

thank you!

[PingPongPay]

@PingPongPay Also, another reason the water is freezing is due to the Joule-Thomson effect... As the vapor is being sucked out of the chamber, the remaining air will cool down. This effect is similar to why a can of compressed air feels cold after cleaning your PC or keyboard. I think most of the cooling would be due to the latent heat and not the Joule-Thomson effect though.

[PingPongPay]

@rudmop The idea that there are "very cold and very hot" molecules in the water is incorrect. Due to heat transfer, each water molecule will have approximately the same kinetic energy. Once the pressure in the chamber is equal to vapor pressure of the water, the water will start to boil. Energy is required for the water to transition from liquid to vapor (this is known as the latent heat of vaporization). As the water boils, it's removing energy from the surrounding water, causing it to cool.

[NamesROverated]

@G8tr1522 i don't think you've ever seen a bong before..

[cris23dumi]

boiling its putting elements in creating collisions freezing is taking them out and they don't look similar

[Zoomer1er]

Mr.Patterson Rocks ! :D ...NOT !

[mattkunq]

@missyrawien

temperature is kinda like a average measurement of kinetic energy of the molecules. So it isnt trickery. There are molecules of water that have different amount of energy than the rest.

[bumblebee1024]

i wont drink a coffee like that

[NukeBluff]

they make it sound too easy to understand