I wrote for Q4(a)(ii) CHEM2 June 2015:
A high operating pressure means that there are more gas particles in a given volume. This means that particles will be more closer together and collide more often. Also, there will be a lot more particles with energy greater than or equal to the activation energy. This means that there will be more frequent successful collisions in a given time so faster rate of reaction.A higher pressure also means that particles will be colliding with each other more and more particles will be moving in a random manner so a faster rate of reaction. As more particles are moving about randomly and there are more particles in a given volume, this will increase the number of frequent successful collisions so a faster rate of reaction.
The mark scheme says:
M1The reaction gets to equilibrium faster / in less time
OR
Produces a small yield faster / in less time
OR
Increases the rate (of reaction / of attainment of equilibrium)
M2 High pressure leads to one of the following
• more particles / molecules in a given volume
• particles / they are closer together
• higher concentration of particles /molecules
AND• more collisions in a given time / increased collision frequency
Is it worth remarking for this mark? I felt I got M1 for a faster rate of reaction and M2 I obviously got. I have bolded what I feel is creditworthy.
Thanks in advance. Ik it's 1 mark but it is 2 UMS. I am also thinking of remarking CHEM1 having got my script back as well.