deltaS/R
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Re: deltaS/R
We don't ignore ∆S/R when deriving the equation. Maybe the term appears to "disappear," but it's actually just cancelled out when we subtract one lnK1 equation from the other (lnK2).
If you're referring to why we can assume ∆S and ∆H are independent of temperature, it is just an assumption we make that isn't exactly true in reality, but allows for simpler estimations.
Hope this cleared things up!
If you're referring to why we can assume ∆S and ∆H are independent of temperature, it is just an assumption we make that isn't exactly true in reality, but allows for simpler estimations.
Hope this cleared things up!
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Re: deltaS/R
When comparing temperatures, deltaS and deltaH are assumed to stay constant for both temperatures which could be why deltaS/R seems to be ignored.
Re: deltaS/R
In the equation you use to compare two temperatures you don't ignore deltaS/R it's just canceled out when subtracting the equations lnK(2)-lnk(1), lnk= (-delta H naught/RT) - (delta S naught/R).
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Re: deltaS/R
Sydney Pell 2E wrote:When comparing temperatures, deltaS and deltaH are assumed to stay constant for both temperatures which could be why deltaS/R seems to be ignored.
Why can you assume that delta S is constant when you're using the van't Hoff equation to compare temperatures?
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Re: deltaS/R
Labiba Sardar 2A wrote:Sydney Pell 2E wrote:When comparing temperatures, deltaS and deltaH are assumed to stay constant for both temperatures which could be why deltaS/R seems to be ignored.
Why can you assume that delta S is constant when you're using the van't Hoff equation to compare temperatures?
We can assume that the delta S (not) is constant because it is the delta S for that specific reaction at standard conditions, so there's only one value for delta S (not). At different temperatures, the delta S (not) at standard conditions is still constant, because it's the value at standard conditions.
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