Kc or Kp for a heterogenenous equilibrium?

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Kc or Kp for a heterogenenous equilibrium?

Take an equilibria such as BF3(g) + 3H2O(l) ⇌ 3HF (aq) + H3BO3 (aq)

In this example, in order to calculate the equilibrium constant, we need the same units for all compounds (ie: molarity/atmospheres). But in this example, would we specifically be calculating Kc or Kp? Or would it not matter provided all the units are the same for the equilibrium expression?

Chris Pleman 3E
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Re: Kc or Kp for a heterogenenous equilibrium?

You have to convert either to only gas (giving you Kp) or only molarity (Kc), so you will need to use the ideal gas law to convert from one to the other.

CameronJohari1J
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Re: Kc or Kp for a heterogenenous equilibrium?

For this example, as long as all the units are the same the equilibrium constant will be the same.