The Student Room Group

A level chem Mc question help

Why is it B and not C ? Liquid has a lower entropy than gas so C is incorrect and thats what they want ?
(edited 8 months ago)
Original post by 1234kelly
Why is it B and not C ? Liquid has a lower entropy than gas so C is incorrect and thats what they want ?

It says which of the following is not True
A - True, Kp is constant at a constant temperature. Change the temperature, change the value of Kp
B - False. Activation energy for a reaction pathway cannot be changed. A catalyst provides an alternate reaction pathway with lower activation energy
C - True for the forward reaction (not the backward reaction) Since you have a gas + liquid going to 2 gases product, increase entropy.
You are correct in identifying it is false for the backward reaction but remember this is equilibrium
So always consider the forward and backward directions
D - True. The reaction involves gaseous water. If the water was liquid, we need more energy to break the bonds to turn it into a gas for the reaction.

Quick Reply

Latest