Delta H

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Peter Nguyen 2I
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Joined: Fri Sep 28, 2018 12:29 am

Delta H

Postby Peter Nguyen 2I » Sun Jan 27, 2019 2:21 pm

What do positive and negative delta H mean?

Christopher Anisi 2K
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Joined: Fri Sep 28, 2018 12:21 am

Re: Delta H

Postby Christopher Anisi 2K » Sun Jan 27, 2019 2:24 pm

A positive delta H indicates that the reaction is endothermic and requires heat to be absorbed while a negative delta H indicates that the reaction is exothermic and releases energy.

Hanniel U 2B
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Re: Delta H

Postby Hanniel U 2B » Sun Jan 27, 2019 2:25 pm

Positive delta H means an Endothermic reaction because is greater than 0. Negative delta H is an exothermic reaction because heat is released.

ryanhon2H
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Joined: Fri Sep 28, 2018 12:28 am

Re: Delta H

Postby ryanhon2H » Sun Jan 27, 2019 2:27 pm

Endothermic is positive ∆H because the enthalpy of the products is greater than the enthalpy of the reactants, so energy is absorbed. The opposite is true for exothermic, since energy is released.

varunhariharan
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Joined: Mon Jan 07, 2019 8:16 am

Re: Delta H

Postby varunhariharan » Sun Jan 27, 2019 3:53 pm

, H being enthalpy. If the enthalpy, or total energy, of the products is greater than the energy of the reactants, then ΔH is positive and it is an endothermic reaction. If the energy of the products is less than the energy of the reactants, ΔH is negative and the reaction is exothermic.

Charles Hood Disc 1C
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Re: Delta H

Postby Charles Hood Disc 1C » Sun Jan 27, 2019 4:06 pm

Delta refers to the change between the final and the initial of value. When you have a negative delta H this is due to the fact that you have lost enthalpy, so it makes sense that the reaction would be exothermic (give off heat). The reverse is true for a reaction with positive delta H. It is an endothermic reaction.

Mhun-Jeong Isaac Lee 1B
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Re: Delta H

Postby Mhun-Jeong Isaac Lee 1B » Sun Jan 27, 2019 4:47 pm

This is how Dr. Lavelle explained it. Positive delta H signifies that it is endothermic which means energy is being put into the system. Negative delta H is exothermic which means energy is leaving the system. In this way, you can rationalize the positive and negative better as gain and loss of energy from the system.

davidryan3f
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Joined: Fri Sep 28, 2018 12:23 am

Re: Delta H

Postby davidryan3f » Sun Jan 27, 2019 4:53 pm

H stands for enthalpy. So delta H represents the change in enthalpy during a reaction. If delta H is positive then the reaction requires energy and is endothermic. If delta H is negative then the reaction releases energy and is exothermic.

isarose0
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Joined: Fri Sep 28, 2018 12:15 am

Re: Delta H

Postby isarose0 » Sun Jan 27, 2019 5:54 pm

positive delta H is endothermic and negative delta H is exothermic

Sheridan Slaterbeck 1J
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Re: Delta H

Postby Sheridan Slaterbeck 1J » Sun Jan 27, 2019 6:05 pm

+H = endothermic the reactions needs heat
-H = exothermic the reaction gives off heat

chrisavalos-2L
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Joined: Fri Sep 28, 2018 12:18 am

Re: Delta H

Postby chrisavalos-2L » Sun Jan 27, 2019 6:20 pm

A positive delta H indicates that the reaction is endothermic and that the reaction takes in heat/energy to occur and if it is negative that means that the reaction is exothermic and releases heat and energy.

Charles Hood Disc 1C
Posts: 39
Joined: Fri Sep 28, 2018 12:19 am

Re: Delta H

Postby Charles Hood Disc 1C » Mon Feb 11, 2019 11:19 pm

A Positive ΔH is an endergonic reaction. A negative ΔH is an exergonic reaction.


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