Interconvert Kp and Kc values. Close Problem Question Content Area Calculate Kp for the following reactions at the indicated temperature.

Question

Interconvert K_p and K_c values.

Calculate K_p for the following reactions at the indicated temperature.

(a)   CO(g) + Cl₂(g) COCl₂(g)  K_c = 99.0 at 593 K

K_p = 

(b)   NH₃(g) + H₂S(g) NH₄HS(s)  K_c = 175 at 300 K

K_p = 

Answer 1

Kp = Kc(RT)^∆n where R = gas constant; T = temperature in Kelvin; ∆n = change in number of moles, i.e. moles of product gas - moles of reactant gas

(a). CO(g) + Cl2(g) <==> COCl2(g) ... Kc = 99.0 @ 593K

Kp = 99.0 (0.0821 * 593)^-1

Kp = (99.0) (48.69)^-1

Kp = 99.0 * 0.0205

Kp = 2.03

(b). NH3(g) + H2S(g) <==> NH4HS(s) ... Kc = 175 @ 300K

Kp = 300 (0.0821 * 300)^-2

Kp = (300)(24.63)^-2

Kp = 300 * 0.201

Kp = 60.4

(be sure to check the math)