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AQA Chemistry AS, will I get any marks for this? Please advise :s

Hi,
Today I did the new specification AS chemistry exam paper 2. Overall I found the paper OKish, but I was wondering if I made a big mistake on the 7 marker.
Basically it asked you to outline the mechanism for the reaction of HBr with some alkene (I forget which one exactly).
Since there was no clear white space provided, as they have included for literally every single mechanism based exam question in the past, and instead only lined paper, I assumed they just wanted you to talk about it, and describe it.
So I described the mechanism in depth, without actually drawing it. Do you think I'll get any marks/would I have a strong case to appeal to the exam board due to this misunderstanding?
Thanks
Hasan

Reply 1

mikeymk

They may give you marks if you correctly identified the electrophile and said that the H-Br gets attacked by the the alkene double bond, I think about 3-4 marks are usually awarded for the arrows, 1 mark per arrow, so you may get 3-4 marks for your description, I did something similar to this once where they asked for the structure and I described it instead of drawing it, since then I always include a little diagram or mechanism, even if they don't ask (if reasonable, I mean for a 1 mark question, I wouldn't thats a bit overboard)

Also, you get a mark for saying what the mechanism is by look at past paper marks schemes, so saying electrophilic addition will have got you at least one mark, the mark scheme I'm looking at atm is for a 5 mark question, where 3 of the marks is for the arrows and so the correct mechanism and the other mark for the correct partial charges, maybe if you mention what the partial charges are, thats another mark.