Question

Write equilibrium constant expressions for K, and Kp for the
formation of nickel tetracarbonyl, which is used to separate nickel from other
impurities:
Ni(s) + 4C0(g) -> Ni(CO), (g)

Answer 1

C'mon. You really need to know how to do this yourself. Here's how you do ALL of them. Kc. Multiply concentrations of the products and divide by the concentraton of the reactants. Then raise EACH product or reactant to a power which is the coefficient in the balanced equation. If it's Kp you want instead of concentrations use partial pressure. For Kc for example:
A + B ==> 2C + 3D
Kc = (C)^2*(D)^3/(A)*(B) or
Kp = pC^2*pD^3/pA*pB OR if you have Kc and want to convert to Kp that can be done this way.
Kp = Kc*(RT)^delta n where delta n = mols procuts-mols reactants. In the case of the equation above that will be (2+3) = (1+1) = 3
Post any follow up questions here and tell me what trouble you're having. This is basic and you need to understand it completely in order to understand what's coming.

Answer 2

oops. typos. See bold/italics where corrected.
Kp = Kc*(RT)^delta n where delta n = mols <b><i>products - mols reactants. In the case of the equation above that will be (2+3) - (1+1) = 3. </b></i>