Exothermic vs. Endothermic

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Alyssa Wilson 2A
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Joined: Fri Sep 28, 2018 12:18 am

Exothermic vs. Endothermic

Postby Alyssa Wilson 2A » Sun Jan 27, 2019 5:49 pm

Can someone please explain the difference between endothermic and exothermic?

Lauryn Shinno 2H
Posts: 59
Joined: Fri Sep 28, 2018 12:24 am

Re: Exothermic vs. Endothermic

Postby Lauryn Shinno 2H » Sun Jan 27, 2019 5:57 pm

Exothermic reactions favor the formation of products and give off heat. Endothermic reactions favor the formation of reactants and require heat.

Yvonne Du
Posts: 64
Joined: Fri Sep 28, 2018 12:23 am

Re: Exothermic vs. Endothermic

Postby Yvonne Du » Sun Jan 27, 2019 6:04 pm

An exothermic reaction has a negative delta H while an endothermic reaction has a positive delta H. Delta H=Change in enthalpy.

Angel Chen 2k
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Joined: Fri Sep 28, 2018 12:20 am

Re: Exothermic vs. Endothermic

Postby Angel Chen 2k » Mon Jan 28, 2019 1:12 am

The two posts before are really standard definitions. In other words, you can simply regard the exothermic reaction as a "releasing heat" process. On the other hand, you can regard endothermic reaction as an "absorbing heat" process.

Jayasuriya Senthilvelan 4I
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Joined: Thu Jan 10, 2019 12:17 am

Re: Exothermic vs. Endothermic

Postby Jayasuriya Senthilvelan 4I » Mon Jan 28, 2019 8:34 am

Exothermic is a reaction that releases heat. Its delta H is negative, < 0. Endothermic is a reaction that absorbs heat from its environment. Its delta H is positive, > 0.

AlyssaBei_1F
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Joined: Fri Sep 28, 2018 12:17 am

Re: Exothermic vs. Endothermic

Postby AlyssaBei_1F » Mon Jan 28, 2019 9:55 am

Endothermic has a positive delta G and exothermic has a negative delta g. Endothermic requires heat and exothermic releases heat. Endothermic favors product formation and exothermic favors reactant formation.

Tony Chung 2I
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Joined: Fri Sep 28, 2018 12:19 am

Re: Exothermic vs. Endothermic

Postby Tony Chung 2I » Mon Jan 28, 2019 3:27 pm

Endothermic: When energy is absorbed from its surroundings. delta H>0
Exothermic: When energy is released. delta H<0

Ashe Chen 2C
Posts: 31
Joined: Mon Jan 07, 2019 8:23 am

Re: Exothermic vs. Endothermic

Postby Ashe Chen 2C » Mon Jan 28, 2019 4:08 pm

If the reaction gives a release of heat (-delta H), the reaction is exothermic. If the reaction requires heat (+delta H), the reaction is endothermic.

Joanna Pham - 2D
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Joined: Fri Apr 06, 2018 11:04 am

Re: Exothermic vs. Endothermic

Postby Joanna Pham - 2D » Tue Jan 29, 2019 6:52 pm

Professor Lavelle gave example of a hot/cold pack during lecture one day, and I thought it was helpful.

Endothermic reactions require heat to obtain the products (delta H = positive) while exothermic reactions release heat during reactions (delta H = negative). Given that, with a hot pack, when you break the bag in inside, it becomes warm. That’s because the bag inside the hot pack undergoes an exothermic reaction, meaning it’s giving off heat which causes the bag to warm up. For the cold pack, upon breaking the bag inside the pack, an endothermic reaction takes place. The reaction absorbs heat from the surrounding and uses to form its products, which is why the pack turns cold.

Hope this helps!

Yiting_Gong_4L
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Joined: Fri Sep 28, 2018 12:25 am

Re: Exothermic vs. Endothermic

Postby Yiting_Gong_4L » Wed Jan 30, 2019 12:11 am

Exothermic reactions release energy, delta H is negative, and heat is a product. Endothermic reactions absorb energy, delta H is positive, and heat is a reactant.

Eva Guillory 2E
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Joined: Fri Sep 28, 2018 12:22 am

Re: Exothermic vs. Endothermic

Postby Eva Guillory 2E » Wed Jan 30, 2019 1:36 pm

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