Pressure Notation

Priscilla Okaiteye
Posts: 61
Joined: Tue Nov 21, 2017 3:02 am

Pressure Notation

When we are writing out the concentrations to find the k constant if not all the products and reactants are gases, do we still use the P notation?

arif_latif_2G
Posts: 60
Joined: Fri Sep 28, 2018 12:23 am

Re: Pressure Notation

If not all chemicals involved are gases, you probably should use molarity rather than partial pressure.

AnnaYan_1l
Posts: 96
Joined: Fri Apr 06, 2018 11:05 am
Been upvoted: 1 time

Re: Pressure Notation

I think Kp is only used when the reaction only includes gases, so I would default to Kc

Tony Ong 3K
Posts: 63
Joined: Fri Sep 28, 2018 12:23 am

Re: Pressure Notation

Kc is regarding molar concentrations whereas Kp is for homogeneous gas equilibria.

If in any case you're required to convert from Kp to Kc or vice versa, you can use the formula:
Kp=Kc(RT)^deltaN

Posts: 33
Joined: Fri Sep 28, 2018 12:22 am

Re: Pressure Notation

When finding Kp, do you have to use a specific unit of pressure? Or can you use any?

Simran Rai 4E
Posts: 58
Joined: Fri Sep 28, 2018 12:17 am

Re: Pressure Notation

Kp should not have any units because it is an activity. ^