Converting Kc to Kp

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JulieAljamal1E
Posts: 71
Joined: Fri Sep 28, 2018 12:24 am

Converting Kc to Kp

Postby JulieAljamal1E » Fri Jan 11, 2019 9:37 am

How do I convert from Kc to Kp or vice versa?

deniise_garciia
Posts: 30
Joined: Wed Nov 16, 2016 3:04 am

Re: Converting Kc to Kp

Postby deniise_garciia » Fri Jan 11, 2019 9:45 am

Kp = Kc (RT)^Dn
P = nRT/V
R = 0.0821 L atm/mol K
T = Temperature in K
Dn = tot. mol product - tot. mol reactant

Not sure if this is the way, but I'm also trying to figure this out. Someone correct me if I'm wrong please!

Chase Yonamine 1J
Posts: 62
Joined: Fri Sep 28, 2018 12:17 am

Re: Converting Kc to Kp

Postby Chase Yonamine 1J » Fri Jan 11, 2019 9:55 am

Just to clarify, Dn is the to total stoichiometric coefficients of the product - the total stoichiometric coefficient of the reactants.
For example, if you had the reaction aA(g)+bB(g)----> cC(g)+dD(g) the Dn would be (c+d)- (a+b).
Also, you are only allowed to use this when the product or the reactant is a gas.
For example, if you had the reaction aA(s)+bB(g)----> cC(g)+dD(aq) the Dn would be (c)- (b).

Edward Suarez 1I
Posts: 75
Joined: Fri Sep 28, 2018 12:27 am

Re: Converting Kc to Kp

Postby Edward Suarez 1I » Fri Jan 11, 2019 10:49 am

PV = nRT
n/v is concentration, so P = concentration * RT

R is a constant while T is typically given, so typically u can just isolate P or concentration and plug it in to a calculator to find P or concentration from a given concentration or P (respectively)

Carissa Young 1K
Posts: 65
Joined: Fri Sep 28, 2018 12:17 am

Re: Converting Kc to Kp

Postby Carissa Young 1K » Fri Jan 11, 2019 10:59 am

To convert, use p=(conc)RT --> Conc=P/(RT). In Module 2, the PCl problem in the video, Lavelle talks about conversion there if you need more assistance.


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