AQA GCSE Chemistry Unit 2 24 May 2012
Chemistry exam discussion - share revision tips in preparation for GCSE, A Level and other chemistry exams and discuss how they went afterwards.
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Re: AQA GCSE Chemistry Unit 2 24 May 2012I think that you would probably get a mark for the oxygen reacting and maybe for the layers (although this is more ambiguous) but I think you might have had to mention electrons for full marks.(Original post by Maat)
for the last question, about the corrosion of the metal, i put something like:
the oxygen react with the metal and this causes disfigurements in the layers which makes it less efficient to conduct electricity, would that get me anything -
Re: AQA GCSE Chemistry Unit 2 24 May 2012I think you'll get both marks. My teacher said something similar to that. Would ionic bonding get any marks. Because it's a metal with a non metal. I also wrote that it would have to be molten or dissolved in water in order to conduct electricity as the ions become free to move around then.(Original post by Maat)
for the last question, about the corrosion of the metal, i put something like:
the oxygen react with the metal and this causes disfigurements in the layers which makes it less efficient to conduct electricity, would that get me anything -
Re: AQA GCSE Chemistry Unit 2 24 May 2012if i wrote hydrogen would i get the mark??(Original post by HopelessTurtle)
Alkaline was OH- ions,
and the other one about the Ph being 1, was H+ ions. -
Re: AQA GCSE Chemistry Unit 2 24 May 2012I think you may have had to say 'hydrogen ions'. Because hydrogen by itself is 'H2' which is incorrect because the H+ ions make the solution acidic.(Original post by werdo1997)
if i wrote hydrogen would i get the mark?? -
Re: AQA GCSE Chemistry Unit 2 24 May 2012balls :/(Original post by kILLERm)
I think you may have had to say 'hydrogen ions'. Because hydrogen by itself is 'H2' which is incorrect because the H+ ions make the solution acidic. -
Re: AQA GCSE Chemistry Unit 2 24 May 2012this is what i put, hopefully i'll get the mark, because i know what it was asking to stated what the two meant(Original post by kILLERm)
I think you may have had to say 'hydrogen ions'. Because hydrogen by itself is 'H2' which is incorrect because the H+ ions make the solution acidic.
1/ what ions made solution x alkali? - Hydroxide or OH-
2/ what ions made the solution have a pH OF 1?- Hydrogen or H+
hopefully ill get the marks! and as for stating " hydrogen or hydroxide ions" it asked you " what IONS" so i think you'd get a mark
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Re: AQA GCSE Chemistry Unit 2 24 May 2012actually, if it asked 'which ions make the solution alkaline/give the solution a pH of 1' then I believe you may get the marks for writing hydrogen and hydroxide because it already told u that they were ions.(Original post by werdo1997)
balls :/ -
Re: AQA GCSE Chemistry Unit 2 24 May 2012yes, i agree it said " which ions"(Original post by kILLERm)
actually, if it asked 'which ions make the solution alkaline/give the solution a pH of 1' then I believe you may get the marks for writing hydrogen and hydroxide because it already told u that they were ions.
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Re: AQA GCSE Chemistry Unit 2 24 May 2012I wrote that the unreacted nitrogen and hydrogen can be reacted again. It also has a 100% atom economy and so no useless products are produced.(Original post by Maat)
Explain why it doesn't matter if a low yield of ammonia is produced in the Haber process (2)
this is because it is a continuous process so it doesn't matter if it does all react because it will go back round to stage 1 again. get the marks? -
Re: AQA GCSE Chemistry Unit 2 24 May 2012If you put OH- first, then that's correct.(Original post by shippers123)
For the " what made solution x alkali" does it matter if you put hydroxide or OH-? I put both will I get marked down for it?
But it's hydroxide ions. I'm sure you'll get the mark though. -
Re: AQA GCSE Chemistry Unit 2 24 May 2012You've definately got 1/2 marks for mentioning that the unreacted nitrogen and hydrogen go back to stage 1. But i'm quite disorientated about what they would've expected you to do for the 2nd mark. That's why I put 2 points down. But you may get 2 marks for mentioning ' unreacted nitrogen and hydrogen' are 'reacted back again/sent to stage 1'. In my opinion, they're 2 valid points and so you should get the marks
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Re: AQA GCSE Chemistry Unit 2 24 May 2012No. They don't mark you down for incorrect content. They reward you for the correct content. So in this case, you have definately given the correct answer and so you've definately got the mark. Stop getting upset about this. Nothing that you put down was incorrect. It just shows that you have a better understanding by mentioning it in both forms. Be proud of yourself cuz I only put H+ and OH- for the questions on pH1 solution and Alkaline solution.(Original post by shippers123)
For the " what made solution x alkali" does it matter if you put hydroxide or OH-? I put both will I get marked down for it? -
Re: AQA GCSE Chemistry Unit 2 24 May 2012But it already said in the question " which ions?"(Original post by x-Sophie-x)
If you put OH- first, then that's correct.
But it's hydroxide ions. I'm sure you'll get the mark though.