Elementary Productions: Solid Nitrogen

In this video, some liquid Nitrogen is placed in a small beaker, which is placed in a vacuum. The behavior of liquid Nitrogen in vacuum is demonstrated

Category:

Science & Technology

Tags:

• nitrogen
• solid
• triple
• point
• vacuum
• pump
• desiccator
• awesome
• chemistry
• interesting
• experiment
• cool
• chemical

[2clickandboom]

we did this with water at my school

[mabakken]

How did you get solid water at reduced pressure?

[2clickandboom]

i dont know exactly what happened but my chemistry teacher put a test tube with water in it in a vaccum chamber and sucked all the air out and then eventually the water just froze, instantaneously. I think it was the evaporation, he said it was a cooling process and thats why it froze.

[mabakken]

hmm...sounds plausible. But then the pressure must have been reduced very rapidly as to ensure an adiabatic change. Is this right?

[derkozten]

How low did the pressure fall?

And the temperature falling is also demonstrated -yet in a far lesser dramatical way- putting water and seeing how it boils at room temperature.

The pressure-freezing point relationship is not that clear. In water/ice, the relationship is inverse, in fact: the higher the pressure, the lower the freezing point. Perhaps with N2 happens the same, but I'm not pretty sure

[mabakken]

I'm guessing around 0,5 Pa.

I've tried the thing with water as well, but it looks cooler with LN2 ;)

I know it's universal for all gases (at RTP) to be solid at extremely high pressures, but water falls under its own category in this regard.

[seanshihtiger]

nice for projects

[yellowmetalcyborg]

@2clickandboom What probably happened was that the water boiled, the test tube cooled becuase the heat that was in the test tube was carried away as steam and eventually there comes a point where the test tube becomes too cold to induce boiling even though the pressure in the tube is very low.

[TakronRust]

@HaroldTheGun You do know N2 has 0 flammability right? If it was flammable we would have blown ourselves up along time ago, seeing as 78 some percent of the atmosphere is nitrogen.

[vmelkon]

@TakronRust well no. It is really a matter of temperature and pressure. At 1 atm and -42 °C, propane boils so you can have liquid propane below that.

[TakronRust]

@vmelkon I'm pretty sure you need to have propane under pressure to liquefy it.

[tyga42]

^^does it still react with copper and iron whilst frozen?

[daenumen]

@mabakken adiabatic?! you want to remove heat from the water, and the cost is you also eject some water from the system.

this is a isochoric process. so heat does pass out from the system.

[BlackSkullRacer613]

Wouldn't the liquid nitrogen cause thermal shock and crack or break the glass beaker?

[MegaRad666]

shouldn't decreasing pressure cause it to expand in an attempt to cover the entire capacity/volume of the vacuum?

[derman077]

@jetsamjetsam speaking from experience? hang on i gotta find a pen to write that down so i dont forget... lol