Gibbs Free Energy Graph - Past Paper Exam Question Walkthrough｜A Level Chemistry (AQA)

[@easymodeexams33]

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[@chrissieeehh2630]

this is legendary! thank you so much :) last chem paper tomorrow and im so excited for this to be done! hope gibbs energy graphs come up!!! again thanks so much:)

[@easymodeexams33]

no worries :) good luck tomorrow!

[@radrue]

lol this is so late but how was it

[@chrissieeehh2630]

@@radrue paper 3 was so good! didnt have the entropy change tho. but it was better than paper 1 and 2. are you doing your alevels this year? :D

[@radrue]

yes and honestly i can't wait for all of this to be over😭 I'm more so stressed about biology rather than chemistry@@chrissieeehh2630

[@ella_mcgov2013]

@@chrissieeehh2630what did you end up getting?

[@stututuutuu]

ur voice is soo calming

[@easymodeexams33]

thnx :)

[@sarajan6690]

Please do more of these and arhenius too!

[@samantharichards607]

Your videos are so helpful! Thank you so much, they’re definitely some of the best I’ve found. Would it be possible for you to cover an AQA transition metal catalysis question? :)

[@easymodeexams33]

Thanks so much for your kind comment! I've skimmed through all current spec AQA past papers and there aren't really any questions on transition metal catalysis other than an equation question about vanadium. If you find one let me know and I'll try to do a video for it. I could try and find an old spec catalysis question from Phys and maths tutor if you'd like?

[@aishahkhan6439]

These videos are amazing but quick question if the gradient given on the graph is positive does that mean delta S is always negative and if the graph has a negative gradient does that mean delta S is always positive ?

[@aurora6758]

well surely if -ΔS = -M you can cancel out the negatives. just follow the equation in the video M = -ΔS, sub in your gradient value and manipulate it. I could be wrong but thats how i would approach it. Good Luck for your next paper

[@easymodeexams33]

yeah, you're correct :) although, try to avoid writing this and instead always make m = -DS in your responses, this will show AQA in your working that you are following the correct method. You always want DS to be positive for your final answer, so you would make the equation DS = -m. If the gradient is positive, then DS will be negative, and if the gradient is negative, DS will = - (-m), which is the same as +m. I hope that makes sense, kinda hard to write out. Pretty much what @aurora6758 said :)

[@MilanFilo-j7u]

elite!

[@ethangolin1289]

how do we know that delta S is negative?

[@uwotm8770]

i love u so so much pls upload more sir

[@easymodeexams33]

thanks! that's the plan haha, doing my best with uploading more :)

[@kalsoom]

legend

[@ar-mo7xc]

The mark scheme doesn’t give a range for the gradient… I got 0.164

[@ar-mo7xc]

0.16428…..

[@easymodeexams33]

What was your final answer? it allows final answer in range -167 to -171, so even though it gives a specific gradient, you will get all marks available if you get a final answer in that range (i.e., range of gradient is given). Hope that makes sense