Kp

The reversible reaction of nitrogen and hydrogen to form ammonia is shown below.
N2(g) + 3H2(g) 2NH3(g)
In the equilibrium mixture, the partial pressure of N2 is 18.75 MPa and the partial pressure of H2 is
2.50 MPa.
The total pressure is 25 MPa.
What is the value of Kp, in MPa−2?
A 1.2 × 10−4
B 0.048
C 0.075
D 21

What I done so far is : 18.75 x (2.5)^3

I am clueless after this :frown:

Reply 1

Mushimedic

all the partial pressures add up to the total pressure so 25 minus (18.75+2.5) which shouldd be 3.75. then do pp of products over pp of reactants. don't forget to add the superscripts so it should be 3.75^2/18.75 x 2.5^3 = 0.048 so B :smile: