Hess's Law

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Timmy Nguyen Dis 1I
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Joined: Sat Aug 17, 2019 12:17 am

Hess's Law

Postby Timmy Nguyen Dis 1I » Sat Jan 25, 2020 11:35 pm

What is this and what can you do with this?

Mulin_Li_2J
Posts: 105
Joined: Sat Aug 17, 2019 12:16 am

Re: Hess's Law

Postby Mulin_Li_2J » Sat Jan 25, 2020 11:48 pm

Basically what Hess's Law says is that enthalpy changes can be additive, mainly because enthalpy is a state property. For a reaction at given temperature and pressure, the enthalpy change of the reaction remains the same no matter how many times you conduct the reaction. So if you know the enthalpy changes for two reactions, then you will know the total change of enthalpy if the two reactions happen together simply by adding them together because enthalpy changes can be additive.

Hope this can help! =_-

Altamash Mahsud 1I
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Joined: Fri Aug 09, 2019 12:16 am

Re: Hess's Law

Postby Altamash Mahsud 1I » Sun Jan 26, 2020 12:15 am

What Hess's law states is that because enthalpy is a state function, enthalpies of reaction can be added together. This means when two or more chemical reactions are added together to get a net reaction, you can get the net enthalpy of reaction by adding the separate enthalpies of reaction of the combined chemical reactions, if that makes sense. 0.0

RobertXu_2J
Posts: 104
Joined: Fri Aug 30, 2019 12:17 am

Re: Hess's Law

Postby RobertXu_2J » Sun Jan 26, 2020 1:04 am

Hess's law states that the total enthalpy change during the complete course of a chemical reaction is the sum of its parts. Basically, it's stating that enthalpy can be added.

RobertXu_2J
Posts: 104
Joined: Fri Aug 30, 2019 12:17 am

Re: Hess's Law

Postby RobertXu_2J » Sun Jan 26, 2020 1:04 am

Hess's law states that the total enthalpy change during the complete course of a chemical reaction is the sum of its parts. Basically, it's stating that enthalpy can be added.

BritneyP- 2c
Posts: 101
Joined: Sat Sep 14, 2019 12:15 am

Re: Hess's Law

Postby BritneyP- 2c » Sun Jan 26, 2020 1:19 am

Hess' law states that enthalpy is a state function which also means that it is additive, meaning 2 or more chemical reactions can be added together.

Veronica Lu 2H
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Re: Hess's Law

Postby Veronica Lu 2H » Sun Jan 26, 2020 11:42 am

Two or more reactions can be added together

Sally Qiu 2E
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Joined: Fri Aug 30, 2019 12:18 am

Re: Hess's Law

Postby Sally Qiu 2E » Sun Jan 26, 2020 12:03 pm

hess's law is basically stating that because enthalpy is a state function, enthalpy is additive. you can simply add the enthalpies of reactions; regardless of how many steps a reaction has, the total enthalpy change is just the sum of all changes


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