Vapor Pressure/Boiling Point/Melting Point

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904914037
Posts: 65
Joined: Wed Sep 18, 2019 12:16 am

Vapor Pressure/Boiling Point/Melting Point

Postby 904914037 » Sat Nov 23, 2019 6:43 pm

Can someone please explain why vapor pressure has a positive correlation with melting point but a negative correlation with boiling point? Do boiling point and melting point have a positive correlation. Thank you!

charleejohnson1L
Posts: 99
Joined: Fri Aug 30, 2019 12:17 am

Re: Vapor Pressure/Boiling Point/Melting Point

Postby charleejohnson1L » Sat Nov 23, 2019 7:02 pm

Something starts boiling when the external pressure is the same as the internal pressure, but something melts when the energy is being absorbed by the solid from to become the melted, liquid form of the substance (the temperature which solid's vapor pressure is equal to the liquid form's vapor pressure). I'm not sure if this helps, but I'm not sure how to actually explain it. :/

JasonKwon_3k
Posts: 51
Joined: Thu Jul 11, 2019 12:16 am

Re: Vapor Pressure/Boiling Point/Melting Point

Postby JasonKwon_3k » Sat Nov 23, 2019 8:47 pm

Melting point is due to the ability of the molecules able to vibrate with energy inputted by heat, eventually reaching the gas state. However, the vapor pressure decreases the distance between the molecules by pushing them together, thus increasing the attractions between them, which increase the boiling point because now it requires more energy to vibrate them to a higher state.


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