ΔS=q/t


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Tamera Scott 1G
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Joined: Fri Sep 28, 2018 12:27 am

ΔS=q/t

Postby Tamera Scott 1G » Wed Feb 13, 2019 10:04 am

When looking at the equation ΔS=q/t, could we say that ΔS=nΔH/T as well?

Nicole Lee 4E
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Re: ΔS=q/t

Postby Nicole Lee 4E » Wed Feb 13, 2019 10:06 am

ΔS=ΔH/T at constant pressure and temperature.

haleyervin7
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Joined: Fri Sep 28, 2018 12:15 am

Re: ΔS=q/t

Postby haleyervin7 » Wed Feb 13, 2019 4:44 pm

What are the requirements to be able to use q/T? Just constant temp?

AdityaGuru1H
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Re: ΔS=q/t

Postby AdityaGuru1H » Wed Feb 13, 2019 8:33 pm

you can use it when t is constant and you can use deltaS=DeltaH/T when pressure is constant

ran2000
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Re: ΔS=q/t

Postby ran2000 » Fri Feb 15, 2019 2:17 pm

This can only be said when pressure is constant since q(at constant pressure)= delta H

Nicholas Le 4H
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Re: ΔS=q/t

Postby Nicholas Le 4H » Fri Feb 15, 2019 2:28 pm

Yes, you can use this when pressure is constant since the change in enthalpy is equal to q when pressure is constant.

Soumya Ravichandran 4H
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Re: ΔS=q/t

Postby Soumya Ravichandran 4H » Fri Feb 15, 2019 2:36 pm

Why can you only calculate delta S, when the q for the reaction is reversible?

Dayna Pham 1I
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Re: ΔS=q/t

Postby Dayna Pham 1I » Sat Feb 16, 2019 5:45 am

Soumya Ravichandran 4H wrote:Why can you only calculate delta S, when the q for the reaction is reversible?


The reaction does not have to be reversible in order to calculate delta S in this way. They just use q rev as a convention, but since delta S is a state function, the pathway doesn’t matter (therefore, it doesn’t matter if it’s reversible or reversible). The only thing we look at is final - initial. Which would be the same for irreversible and reversible.

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

Re: ΔS=q/t

Postby Ashe Chen 2C » Sat Feb 16, 2019 9:54 pm

when pressure and temperature are constant,


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