GCSE CHEM- mark scheme. Is this an error?

OK I can't post photos but it's an exothermic reactions
Specimen paper 2018 combined science

It shows reaction profile fir exothermic reaction
Where di we draw overall energy change???

I thoight it was from reactants to products but they drew it from peak of curve to base

Reply 1

Pigster

Original post by labyr5nth

OK I can't post photos but it's an exothermic reactions
Specimen paper 2018 combined science
It shows reaction profile fir exothermic reaction
Where di we draw overall energy change???
I thoight it was from reactants to products but they drew it from peak of curve to base

Which exam board?

Reply 2

labyr5nth

Original post by Pigster

Which exam board?

Aqa

Reply 3

TypicalNerd

It would appear you've asked about Q6.1

https://mmerevise.co.uk/app/uploads/2023/08/AQA-GCSE-Combined-Science-Trilogy-Chemistry-Higher-Paper-1-Specimen.pdf

https://mmerevise.co.uk/app/uploads/2023/08/AQA-GCSE-Combined-Science-Trilogy-Chemistry-Higher-Paper-1-Specimen-Mark-Scheme.pdf

The arrow itself is correctly placed because the levels corresponding to the energies of the reactants and products have been extended and the arrow has been drawn between the extensions of these lines.

However, there is actually a small error in the mark scheme in that the overall energy change arrow shouldn't point both up and down. It's an exothermic reaction and so really it should point downwards only and if this were an A level question instead, the answer given would actually lose a mark.

(edited 3 months ago)

Reply 4

labyr5nth

Original post by TypicalNerd

It would appear you've asked about Q6.1
https://mmerevise.co.uk/app/uploads/2023/08/AQA-GCSE-Combined-Science-Trilogy-Chemistry-Higher-Paper-1-Specimen.pdf
https://mmerevise.co.uk/app/uploads/2023/08/AQA-GCSE-Combined-Science-Trilogy-Chemistry-Higher-Paper-1-Specimen-Mark-Scheme.pdf
The arrow itself is correctly placed because the levels corresponding to the energies of the reactants and products have been extended and the arrow has been drawn between the extensions of these lines.
However, there is actually a small error in the mark scheme in that the overall energy change arrow shouldn't point both up and down. It's an exothermic reaction and so really it should point downwards only and if this were an A level question instead, the answer given would actually lose a mark.