A Level Chemistry 2017 Paper 1 Question 10 Solution - Exclusive

In this exclusive video we want to discuss the suggested solution for A Levels Chemistry (H2 Chemistry) 2017 Paper 1 Question 10.

Let's take a look at this question:

2017 A Level H2 Chemistry Paper 1 Question 10

The topic tested in this question is on Thermodynamics.

We need to consider all the statements and see which statement can explain why the process of diamond to graphite is not feasible.

Statement One

The first statement is involving an extremely small rate constant is linked to kinetic feasibility.

Since the rate constant is extremely small, the rate of reaction is extremely slow.

This means that the reaction is kinetically not feasible.

However we do not have the information in this question to prove this, so we have to put this as a "maybe" first.

Statement Two

The second statement is involving the standard Gibbs Free Energy of the reaction.

The standard enthalpy change and standard entrophy change of the process of diamond to graphite is given in the question, so we can use this to calculate the standard Gibbs Free Energy of the process.

2017 P1Q10 Gibbs free energy equation

On calculation we can verify that the standard Gibbs Free Energy is negative, but this would imply that the reaction is thermodynamically feasible.

Therefore we have to rule out statement 2, as the question states that the reaction is in fact not feasible.

Statement Three

The third statement talks about the feasibility of the reverse reaction of graphite to diamond.

Now if this process is spontaneous, everyone can buy some graphite and put it on your study table and wait for it to convert to diamond!

Of course this doesn't happen, and we can rule statement 3 out as well.

Finally we can combine our conclusions:

Statement 1 - maybe

Statement 2 - no

Statement 3 - no

So we have to treat Statement 1 as a yes otherwise there will be no correct answer.

Finally we can compare the options A to D and determine the correct answer is B

Check out this video for the full solution and detailed calculation!

Topic: Thermodynamics, Physical Chemistry, A Level Chemistry, Singapore

Found this A Level Chemistry video useful?

Please LIKE this video and SHARE it with your friends!

You might also be interested in this video on A Level Chemistry 2017 Paper 1 Question 9 Solution.

Check out other A Level Chemistry Video Lessons here!

Looking for H2 Chemistry Tuition? Do consider taking up my classes at Bishan or online classes!