Question

Establish relation between Kp and Kc.​

Answer 1

Kp And Kc
Kp And Kc are the equilibrium constant of an ideal gaseous mixture. Kp is equilibrium constant used when equilibrium concentrations are expressed in atmospheric pressure and Kc is equilibrium constant used when equilibrium concentrations are expressed in molarity.

For many general chemical reactions aA + bB ⇋ cC + dD

Where a mole of reactant A

b mole of reactant B

c mole of product C

d mole of product D

Consider an example

2A(g)+B(g) ⇋ 2C(g) All in the gas phase.

The Kp is given by-

Kp=P2CP2APB ———(1)


PV = nRT

On rearranging we get-

P=nVRT
Substituting these in equation (1)

⇒Kp=[C]2(RT)2[A]2(RT)2[B](RT) ⇒Kp=[C]2[A]2[B]×(RT)2(RT)2(RT)
On canceling like terms and substituting Kc=[C]2[A]2[B] we get-

⇒Kp=KcRT


hope this will help

Answer 2

Answer:

Then Kp=Kc. Case-2: If the change in the number of moles of gas molecules is positive, i.e., if Δng > 0 then, Kp>Kc.