In: Chemistry
Will literally worship you if you can give me some assistance with these. (I rate immediately)
Consider the reaction. A(g)⇌2B(g) Find the equilibrium partial pressures of A and B for each of the different values of Kp. Assume that the initial partial pressure of B in each case is 1.0 atm and that the initial partial pressure of A is 0.0 atm. Make any appropriate simplifying assumptions.
Part A
Kp= 1.6
Part B
Kp= 1.5×10−4
Part C
Kp= 1.6×105
Part A)
Given, the equilibrium reaction,
A(g) 2B(g) -------Kp = 1.6
PA = 0.0 atm
PB = 1.0 atm
Reversing the reaction,
2B(g) A(g)
2B(g) | A(g) | |
I(atm) | 1.0 | 0 |
C(atm) | -2x | +x |
E(atm) | 1.0-2x | x |
Now, Kp' = 1 /Kp
Kp' = 1 /1.6
Kp' = 0.625
Now, the Kp' expression is,
Kp' = PA / PB2
Kp' = x / (1-2x)2
0.625 = x / ( 1 -4x +4x2)
0.625 - 2.5x + 2.5x2 = x
2.5x2 - 3.5 x + 0.625 = 0
Solving the quadratic equation,
x = 0.2101
Thus,
PA = x = 0.21 atm [ 2s.f]
PB = ( 1-2x) = 0.58 atm [2 s.f]
Part B)
Given, the equilibrium reaction,
A(g) 2B(g) -------Kp = 1.5 x 10-4
PA = 0.0 atm
PB = 1.0 atm
Reversing the reaction,
2B(g) A(g)
2B(g) | A(g) | |
I(atm) | 1.0 | 0 |
C(atm) | -2x | +x |
E(atm) | 1.0-2x | x |
Now, Kp' = 1 /Kp
Kp' = 1 /(1.5 x 10-4)
Kp' = 6666.667
Now, the Kp' expression is,
Kp' = PA / PB2
Kp' = x / (1-2x)2
6666.667 = x / ( 1 -4x +4x2)
6666.667 - 26666.67x + 26666.67x2 = x
26666.67x2 - 26667.67x + 6666.667 = 0
Solving the quadratic equation,
x = 0.50
Thus,
PA = x = 0.50 atm [ 2s.f]
PB = ( 1-2x) = 0.0 atm
Part C)
Given, the equilibrium reaction,
A(g) 2B(g) -------Kp = 1.6 x 105
PA = 0.0 atm
PB = 1.0 atm
Reversing the reaction,
2B(g) A(g)
2B(g) | A(g) | |
I(atm) | 1.0 | 0 |
C(atm) | -2x | +x |
E(atm) | 1.0-2x | x |
Now, Kp' = 1 /1.6 x 105
Kp' = 1 /(1.5 x 10-4)
Kp' = 6.25 x 10-6
Now, the Kp' expression is,
Kp' = PA / PB2
6.25 x 10-6 = x / (1-2x)2
6.25 x 10-6 = x / (1)2 ------Here (1-2x) 1 Since, x<<< 1
x = 6.25 x 10-6
Thus,
PA = x = 6.2 x 10-6 atm Or 6.3 x 10-6 atm [ 2s.f]
PB = ( 1-2x) = 1.0 atm Or 0.99 atm