1sir but wont the pressure at equilibrium depend on the state of eq,(i mean a+b-2x) which will be constant for a particular value of equilibrium constant .the pressure is found out using the other conditions at eq
N2 + 3 H2 → (equilibrium) 2NH3
is a gaseous phase equilibrium reaction taking place in a 5-litre flask at 400 K. For this choose the correct alternative :
A) Kc = Kx B) Kc = 25 Kx
C) Kx = 25 Kc D) Kc = 5 Kx
-
UP 0 DOWN 0 0 8
8 Answers
1Kx is the equilibrium constant w.r.t the mole fractions of each substance at equilibrium.
Kp = Kc(RT)Δn
Kp = Kx pΔn
1N2 + 3H2 = 2NH3
a b 0
a-x b-3x 2x
KC = ( 2x/500)2
____________
(a-x/500)*(b-X/500)3
TOTAL NO OF MOLES AT EQ.= (a+b-2x)
TOTAL PRESSURE AT EQ= (a+b-2x) R 400
__________
500
PARTIALL PRESSURE OF N2=(a+b-2x)*R*400*(a-x)
____________________
500*(a+b-2x)
SIMILARLY, FIND PARTIAL PRESSURES OF OTHERS AND FIND KP. IT WILL BE FREE OF (a+b-2x).SO CAN BE COMPARED TO KC
1357Kx is not a fixed quantity. It depends on the total pressure of the system.
So for the reaction, we can't tell unless the total pressure is given
11dont need to know that. kp /kx is coming out to be a fixed quantity