## K and Kc

Jacqueline Duong 1H
Posts: 61
Joined: Fri Sep 28, 2018 12:28 am

### K and Kc

What is the difference between K and Kc, and when do we know to use which one?

Sara Lakamsani 4D
Posts: 61
Joined: Fri Sep 28, 2018 12:29 am

### Re: K and Kc

K can be used interchangeably to refer to the equilibrium constant using partial pressures or concentration. Sometimes you will see Kp when using partial pressures or Kc when using concentrations. If there is no subscript, partial pressures are probably being used, but you should be able to tell based on the info they give you in the problem.

Sara Lakamsani 4D
Posts: 61
Joined: Fri Sep 28, 2018 12:29 am

### Re: K and Kc

Hope this helps!

mbaker4E
Posts: 69
Joined: Fri Sep 28, 2018 12:26 am

### Re: K and Kc

K and Kc can be the same thing, but Kc refers specifically to concentration while Kp refers to partial pressures.

lukezhang2C
Posts: 59
Joined: Fri Sep 28, 2018 12:18 am

### Re: K and Kc

K and Kc can mean similar things depending on the context of the problem, but Kp would mean partial pressures while Kc would mean concentration.

Gillian Ward 1F
Posts: 61
Joined: Fri Sep 28, 2018 12:27 am

### Re: K and Kc

K and Kc are basically the same thing, except that Kc specifically means concentrations like Kp would refer to partial pressures.

paytonm1H
Posts: 74
Joined: Fri Sep 28, 2018 12:18 am

### Re: K and Kc

Kc is the equilibrium constant with respect to the equilibrium concentrations. Kp is with respect to equilibrium partial pressures (for gases). K is one of these two.