Kc vs. Kp [ENDORSED]

[Shanzey]

How do we know when to use Kc or when to use Kp? Does it need to be specified which we are using, or do we have to assume that Kp applies to things in the gas phase (since it deals with partial pressure), while Kc typically is used for aqueous solutions?

[DesireBrown1J]

Yes, K_P applies to gases with partial pressures and K_C is for aqueous solutions or gases with molar concentration.

[Cindy Adiwidjaja 1B]

When dealing with gases, we assume that we have to use Kp since gases have pressure. When dealing with aqueous solutions, we assume that we use Kc since aqueous solutions have concentrations.

[MaggieHan1L]

Yes when we see gas we assume Kp and when we see aqueous we assume Kc.

[Jessica Li 4F]

Kc applies to molar concentration (M) of gases or aqueous solutions, while Kp applies only to gases and is respective to their partial pressures.