Enthalpy of Vaporization and Fusion

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Ryan Chang 1C
Posts: 105
Joined: Sat Aug 24, 2019 12:17 am

Enthalpy of Vaporization and Fusion

Postby Ryan Chang 1C » Sun Jan 26, 2020 10:53 pm

Why is the enthalpy of vaporization greater than the enthalpy of fusion.

ABombino_2J
Posts: 102
Joined: Thu Jul 11, 2019 12:15 am

Re: Enthalpy of Vaporization and Fusion

Postby ABombino_2J » Sun Jan 26, 2020 10:56 pm

The energy required to turn a liquid into a gas is a lot more than the energy that is required to turn a solid into a liquid.

Myka G 1l
Posts: 100
Joined: Fri Aug 30, 2019 12:17 am

Re: Enthalpy of Vaporization and Fusion

Postby Myka G 1l » Sun Jan 26, 2020 11:00 pm

The enthalpy of vaporization is greater than the enthalpy of fusion because during a phase change the molecules are separated and the energy required to completely separate the molecules from a liquid to gas is much greater that if you were just to reduce their separation when converting from solid to liquid.

Long Luong 2H
Posts: 51
Joined: Thu Sep 19, 2019 12:16 am

Re: Enthalpy of Vaporization and Fusion

Postby Long Luong 2H » Sun Jan 26, 2020 11:04 pm

It may help to visualize the molecules that make up a solid, liquid and gas. When turning a solid to a gas, the molecules are more freely moving, but still packed together. However, when you turn a liquid into a gas, you are energizing the molecules so that they are quickly bouncing around completely free.

ASetlur_1G
Posts: 101
Joined: Fri Aug 09, 2019 12:17 am

Re: Enthalpy of Vaporization and Fusion

Postby ASetlur_1G » Sun Jan 26, 2020 11:06 pm

Water in its liquid state has strong intermolecular force (hydrogen bonding), but water in its vapor phase has almost no intermolecular force. Thus, it takes a lot of energy to break the hydrogen bonds for water in liquid phase to turn to water in vapor phase. For fusion, the intermolecular forces aren't completely destroyed, but the intensity of the force is decreased. It takes less energy to weaken the force to convert water in solid state to water in liquid state.

Shrayes Raman
Posts: 129
Joined: Sat Jul 20, 2019 12:15 am

Re: Enthalpy of Vaporization and Fusion

Postby Shrayes Raman » Mon Jan 27, 2020 12:04 am

Solid to liquid is relatively low energy but liquid to gas is much higher.


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