Phase changes: endothermic vs exothermic

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705279989
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Phase changes: endothermic vs exothermic

Postby 705279989 » Wed Jan 22, 2020 3:53 pm

Would the reverse reactions of vaporization, melting, and sublimation be exothermic?

Abhi Vempati 2H
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Re: Phase changes: endothermic vs exothermic

Postby Abhi Vempati 2H » Wed Jan 22, 2020 4:02 pm

Yes, the reverse reactions (condensation, freezing, and deposition) would be exothermic because they release energy, forming a more stable phase of matter.

Kayli Choy 2F
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Re: Phase changes: endothermic vs exothermic

Postby Kayli Choy 2F » Thu Jan 23, 2020 2:23 pm

Bond formation is typically exothermic (condensation, freezing, deposition), and bond breaking is typically endothermic (melting, vaporizing, sublimation).

Norman Dis4C
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Re: Phase changes: endothermic vs exothermic

Postby Norman Dis4C » Sun Jan 26, 2020 12:28 pm

Yes, the opposite of these process is condensation, freezing, and deposition respectively, which are all exothermic.

Matt F
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Re: Phase changes: endothermic vs exothermic

Postby Matt F » Sun Jan 26, 2020 1:50 pm

The energy change in the reverse reaction will always be the opposite of the forward reaction since the heat curve is flipped. So the reverse reaction for something endothermic such as vaporization would be exothermic

Natalie Benitez 1E
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Re: Phase changes: endothermic vs exothermic

Postby Natalie Benitez 1E » Sun Jan 26, 2020 3:11 pm

Why would the reverse reaction of vaporization, melting and sublimation be exothermic?

Anokhi Patel 2B
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Re: Phase changes: endothermic vs exothermic

Postby Anokhi Patel 2B » Sun Jan 26, 2020 4:27 pm

yes the reverse reaction, condensation, solidification, and deposition are all exothermic where they expel heat energy going from higher energy phases to lower energy phases.

Andres Merlos 2L
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Re: Phase changes: endothermic vs exothermic

Postby Andres Merlos 2L » Sun Jan 26, 2020 4:35 pm

Yes, it is important to note that the reverse of those reactions are condensation, freezing, and deposition, respectively. Condensation, freezing, and deposition are bond forming, which is why they would be exothermic. Bond breaking, on the other hand, would include vaporization, melting, and sublimation. These would be endothermic.

Frank He 4G
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Re: Phase changes: endothermic vs exothermic

Postby Frank He 4G » Sun Jan 26, 2020 4:39 pm

Natalie Benitez 1E wrote:Why would the reverse reaction of vaporization, melting and sublimation be exothermic?


Well first, the reason why vaporization, melting, and sublimation are endothermic is because bonds are being broken, which takes energy to happen. So in the reverse reaction, bonds are being formed, and it is exothermic because forming bonds releases energy.

Kavya Immadisetty 2B
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Re: Phase changes: endothermic vs exothermic

Postby Kavya Immadisetty 2B » Sun Jan 26, 2020 4:51 pm

yes, the reverse of endothermic reactions are exothermic and vice versa

Megan Kirschner
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Re: Phase changes: endothermic vs exothermic

Postby Megan Kirschner » Sun Jan 26, 2020 7:10 pm

So essentially: endo is adding energy/heat, and exo is when heat/energy is released

Alondra
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Re: Phase changes: endothermic vs exothermic

Postby Alondra » Sun Jan 26, 2020 7:52 pm

Yes! Reverse rxns are exothermic!

Exothermic: condensation, freezing, deposition

Endothermic: vaporization, melting, sublimation

504939134
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Re: Phase changes: endothermic vs exothermic

Postby 504939134 » Sun Jan 26, 2020 9:53 pm

Reverse reactions are exothermic because heat is not required, in fact heat is released when going in the reverse reaction.


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