What is Kp?

For the reaction
2A(g)+2B(g)⇌C(g)

Kc = 34.8 at a temperature of 19 ∘C .

1 Answer
Feb 26, 2018

#Kp = 0.00253#

Explanation:

#Kp = Kc(RT)^(∆n)#

Where:
#Kp# is the equilibrium constant for partial pressure
#Kc# is the equilibrium constant for concentration
#R = 0.08206 "L*atm"/"mol*K"# (it's a constant)
#T# is the temperature (in Kelvin)
#∆n# is the change in the number of mols (number of mols of products in balanced reaction equation - number of mols in of reactants in balanced reaction equation)

We know that
#Kp# is unknown
#Kc# = 34.8
#R = 0.08206 "L*atm"/"mol*K"#
#T = 19˚C + 273.15 = 292.15 "K" ( this is how you convert from C˚ to K) #∆n = 1 "mol" - 4 "mol" = -3 "mol"#

Plugging in the information we then have:

#Kp = 34.8(0.08206 "L*atm"/"mol*K"*292.15"K")^(-3"mol")#

#Kp = 0.00253#