reaction entropy

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Kyle Rex 1K
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reaction entropy

Postby Kyle Rex 1K » Thu Feb 13, 2020 9:59 pm

is solving for reaction entropy like the same as solving for reaction enthalpy where its the sum of products molar entropy - sum of reactants molar entropy or is there another formula we have to use?

Zaynab Hashm 2I
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Re: reaction entropy

Postby Zaynab Hashm 2I » Thu Feb 13, 2020 10:23 pm

we use, ΔS° = ΣS°(products) - ΣS°(reactants), and i think we can also calculate ΔS using some of the formulas found on the formula sheet, but that depends on what is known/unknown and the system of the reaction

Ariel Davydov 1C
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Re: reaction entropy

Postby Ariel Davydov 1C » Fri Feb 14, 2020 8:08 am

You can also calculate deltaG the same way.

Kaitlyn Ang 1J
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Re: reaction entropy

Postby Kaitlyn Ang 1J » Fri Feb 14, 2020 9:53 am

Ariel Davydov 1C wrote:You can also calculate deltaG the same way.

I think for any state function you can calculate it this way because all we care about is the change from initial to final so in reactions, the “final” stage is the products and the “initial” stage is the reactants, so you would do products - reactants, which is what you do for deltaS, deltaG, and deltaH

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Re: reaction entropy

Postby JasonLiu_2J » Fri Feb 14, 2020 12:00 pm

Since entropy, like enthalpy, is a state function, you can find entropy of reaction by doing standard entropy of products minus the standard entropy of the reactants (multiplying each by the stoichiometric coefficients. It's also good to know that for enthalpy and Gibbs free energy, you are using the enthalpy of formation and gibbs free energy of formations, respectively, whereas for entropy, you are using the standard molar entropies of the reactants and products.

Madelyn Romberg 1H
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Re: reaction entropy

Postby Madelyn Romberg 1H » Sun Feb 16, 2020 8:51 pm

It will be the products minus the reactants to find the net change. This applies to other state functions as well.

Eesha Chattopadhyay 2K
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Re: reaction entropy

Postby Eesha Chattopadhyay 2K » Sun Feb 16, 2020 9:00 pm

Yes, this can be done because it is also a state function.

Anna Chen 1K
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Re: reaction entropy

Postby Anna Chen 1K » Sun Feb 16, 2020 9:08 pm

You can use the equation ΔS° = ΣS°(products) - ΣS°(reactants) to solve for entropy of a reaction since entropy is a state function.

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