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When asked to write an equation... (AQA Chemistry) May be Obvious..

Hi


It'd be great if someone could advise please, as I'm in a bit of a muddle and it may be one of those obvious questions that isn't dawning on me.
When I do past papers it often states to write an equation, I've got into a habit of drawing out the reactants and products of the equation. I find this easier and you don't have to learn the molecular formulas( by this I mean my molecular formula never matches the one in the mark scheme).
Would this be penalised?

Thanks :smile:
Reply 1
Original post by Cupcakez18
Hi


It'd be great if someone could advise please, as I'm in a bit of a muddle and it may be one of those obvious questions that isn't dawning on me.
When I do past papers it often states to write an equation, I've got into a habit of drawing out the reactants and products of the equation. I find this easier and you don't have to learn the molecular formulas( by this I mean my molecular formula never matches the one in the mark scheme).
Would this be penalised?

Thanks :smile:


What do you mean by drawing?

What level are you studying at? GCSE/A-Level?

:h:
Reply 2
Hi
Thanks for replying.
By drawing I mean doing the displayed formula. I'm studying A level.
Reply 3
Original post by Cupcakez18
Hi
Thanks for replying.
By drawing I mean doing the displayed formula. I'm studying A level.


Then surely you can write the molecular formula? I'm confused :frown:

If it doesn't specify which type of formula to use, doing that is probably fine.

In OCR Chem A you are usually told a formula to use (in which case, yes, you would be penalised for using the wrong one), but I'm not sure which exam board you're on, so it may be different :yep:
Reply 4
Original post by Neuth
Then surely you can write the molecular formula? I'm confused :frown:

If it doesn't specify which type of formula to use, doing that is probably fine.

In OCR Chem A you are usually told a formula to use (in which case, yes, you would be penalised for using the wrong one), but I'm not sure which exam board you're on, so it may be different :yep:


I think its obvious I don't explain myself very well :smile:

It doesn't specify in the question I'm doing the AQA exam board.

for example if I needed to write the formula for ethanoic anhydride I'd write CH3COOCOCH3 but in the mark scheme it'd say (CH3CO)^2 O. I know that they're the same but I worry I'd be penalised. There's lot of instances where I've written the formula backwards/differently to them.
Reply 5
Original post by Cupcakez18
I think its obvious I don't explain myself very well :smile:

It doesn't specify in the question I'm doing the AQA exam board.

for example if I needed to write the formula for ethanoic anhydride I'd write CH3COOCOCH3 but in the mark scheme it'd say (CH3CO)^2 O. I know that they're the same but I worry I'd be penalised. There's lot of instances where I've written the formula backwards/differently to them.


Ah, I see what you mean - you do the shorthand/condensded formula and they've written the molecular formula.

Does it not say anything about it in the mark schemes? :dontknow:

I wouldn't think they could mark you wrong for using a different type of formula, but I'm not too sure what AQA Chem is like - maybe you're meant to put molecular for everything or something?

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