# CIE A-levels Chemistry

A reaction involved in the Contact process is shown.
2SO2(g) + O2(g)==> 2SO3(g) ∆H= –197kJ mol–1
The reaction is investigated at 200 kPa and 700K and the value of the equilibrium constant, Kp, is
found to be Y. The reaction is then investigated at 1000 kPa and 700K and the value of Kp is
found to be Z.
Which statement comparing Y and Z is correct?
A Y and Z are the same.
B Y is greater than Z.
C Z is 2.2 times greater than Y.
D Z is 5.0 times greater than Y.

Please explain to me why the answer is A. Really appreciate it. My AS exam is next week...sorry if i'm posting too many questions...just need to be clear with these types of questions
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the answer is A as Kp and Kc is only affected by temperature.
Thank you
Original post by Tetisya
A reaction involved in the Contact process is shown.
2SO2(g) + O2(g)==> 2SO3(g) ∆H= –197kJ mol–1
The reaction is investigated at 200 kPa and 700K and the value of the equilibrium constant, Kp, is
found to be Y. The reaction is then investigated at 1000 kPa and 700K and the value of Kp is
found to be Z.
Which statement comparing Y and Z is correct?
A Y and Z are the same.
B Y is greater than Z.
C Z is 2.2 times greater than Y.
D Z is 5.0 times greater than Y.
Please explain to me why the answer is A. Really appreciate it. My AS exam is next week...sorry if i'm posting too many questions...just need to be clear with these types of questions

The answer is A because the value of Kp is only affected by the temperature.
Here in the question, the temperature for both remain the same which is 700K, so the value of Kp of Y and Z are equal.