Edexcel AS Chemistry Unit 2 Thread

The answer could just be that because the process must be very quick a high temperature is needed otherwise the reaction rate would be too slow so it is a compromise between maximum yield and rate of reaction?

i dont recall this question where was it like what part of hwat question

ALL EDEXCEL JUNE CHEM PAPERS HERE: http://www.thestudentroom.co.uk/showthread.php?t=1330409

and where are the mark schemes ?? please

they're coming out on the 21st.

the answer is 6.72 g/dm u are all dumb my teacher went through it and done it himself lol and he has a phD do you have a phd sorry no

Oh my my my...markschemes are out(posted by doughboy) and it don't make pretty reading.

I took unit 1 in Jan and got 91/120 (B) and all past papers for unit 2 I did, scored over 85% in all cases...then I sat the exam and I knew it was going to be a 'long' exam from when I got stuck on the multiple choice Q's..then cam that bloody mole calculation question OMG..am I the only thicko coz I couldn't do it to save my life.

Now reverting baqck to this markscheme released by edexcel I can't believe how tight the marks seem to be....have a look!

It was tricky to say the least this paper just in the case of the question of the Buckminister fullerence multiple choice Q. I was certain it was delocalised e- and the answer was higher sublimes....reckon I got 45/80....I need 69UMS for an A as I got 40/40 for Unit 3.........plsssssssssssssssssssssssssss

lol fail, i got 59/80 for this paper and got a low B, they also marked me 0 for stating that cfc is 'chlorofluorocarbon compound'

Happy with that test. I'll hopefully get 64/80. Test was fairly easy and so I'm expecting the grade boundaries to be HIGH!

In my book it says that as the difference in electro negativity increases, the molecule becomes more and more Ionic. For a compound to be covalent, the difference in electronegativities has to be under 1.5.

I was surprised with the mechanism question as I thought that was part of unit 1 and totally messed that question up.

I had no idea what CFC stood for and so just made up an answer:

Chloro-Fluoro-Carbon

WOuld that be right?