Cambridge Chemistry Challenge Lower Sixth!

I did this Thursday. Wasn't in yesterday so haven't heard. Probably didn't do too well, because we weren't allowed IR absorption data... So how on earth was I meant to suggest structures and functional groups?!

If I had a book I'd have done a lot better I think :frown:

Yeah, that question with IR, the IR data table must not be allowed, however some other classes in my college, my friends are given that table but not my class. if you had that IR data, you would have had 6 free marks.

Reply 21

L'Evil Fish

18

Original post by than4711

Yeah, that question with IR, the IR data table must not be allowed, however some other classes in my college, my friends are given that table but not my class. if you had that IR data, you would have had 6 free marks.

But I couldn't do the Organic properly either without knowing :frown:

Reply 22

username1123194

The IR spectra could be worked out easily if you did the other part of the question, to do with drawing the structure of compounds at each stage, if you managed to do that then it's simply an elimination process and look at similarities in functional group between compounds with the same IR wave-numbers.
Hah, I think I messed up the easiest question... about the oxidation number of silicon... I put -4 instead of +4 >.<

Reply 23

L'Evil Fish

18

Original post by LeoMantys

The IR spectra could be worked out easily if you did the other part of the question, to do with drawing the structure of compounds at each stage, if you managed to do that then it's simply an elimination process and look at similarities in functional group between compounds with the same IR wave-numbers.
Hah, I think I messed up the easiest question... about the oxidation number of silicon... I put -4 instead of +4 >.<

Yeah that's what I tried doing, but it was 5pm and I couldn't be bothered lol

Reply 24

Wesbian

1

Original post by LeoMantys

The IR spectra could be worked out easily if you did the other part of the question, to do with drawing the structure of compounds at each stage, if you managed to do that then it's simply an elimination process and look at similarities in functional group between compounds with the same IR wave-numbers.
Hah, I think I messed up the easiest question... about the oxidation number of silicon... I put -4 instead of +4 >.<

I put -4 too, are you sure that's wrong :redface:

?

Posted from TSR Mobile

mark scheme anyone?

Original post by Wesbian

I put -4 too, are you sure that's wrong :redface:

?

Posted from TSR Mobile

I think so... well I searched it on Google and it said that 4+ is more common... but then I found the ore from which beryllium is more commonly extracted and it had more than 1 oxygen (emperical formlua) in it (I put x=1 for the number of oxygen in the ore resulting through assigning oxidation states) and so it meant that Si would have an oxidation number of -4 in the one on the web... but idk if they will accept it or not... :P
I thought that the oxidation state of Si in SiO2 was 4+ however this was covalent... maybe the more likely scenario would me in ionic compounds such as Al₂Be₃Si₆O₁₈_{where the oxidation state is -4... however in this the silicon is written on the left hand side (which usually means it has a positive oxidation number alphabetically) now that I come to think of it in the question it was written on the right hand side of oxygen... so maybe we're right :P}

(edited 9 years ago)

Reply 27

BP_Tranquility

5

I did this challenge last week, I got around 18 marks which is probably a copper :redface:

Reply 28

username2052143

Hi, just got marks back today and I got 39, is that any good? Was told about it on the day haha and never seen the paper before so don't know the point of it?? :s-smilie:

Reply 29

cookiemonster15

17

Erm yeah!!!! That's AMAZING. Those tests are really hard. I only got 11 so I think you did brilliantly!

Reply 30

Laura1526

Is anyone doing the exam this year?

Reply 31

cleggj88

5

Original post by Laura1526

Is anyone doing the exam this year?

I will be

Reply 32

Laura1526

Original post by cleggj88

I will be

How did you prepare? Im finding it quite hard because ive heard that there will be stuff from A2 as well as AS.

Reply 33

cleggj88

5

The past papers from previous years

Reply 34

Chickenfoot20

1

Do you guthe grade boundatirs are sent out

Reply 35

orporman

3

I did the paper on Thursday my teacher unofficially marked it at 47/60 and it's getting sent off. Expecting a few marks taken off because he was lenient with error carried forward with the synthesis question, but I'm still fairly chuffed! 😊

Reply 36

Chickenfoot20

1

Original post by orporman

I did the paper on Thursday my teacher unofficially marked it at 47/60 and it's getting sent off. Expecting a few marks taken off because he was lenient with error carried forward with the synthesis question, but I'm still fairly chuffed! 😊

Nice! I got the same (although i have reason to believe i got marked up - no confirmation though :s-smilie:

). Did you hear if you got roentgenium?

Reply 37

jmsk_

12

Anyone doing it this year?

Reply 38

9332

1

Yes, But not sure when, as might do it on monday or tuesday. has anyone done it yet?

Reply 39

username2345291

21

Original post by 9332

Yes, But not sure when, as might do it on monday or tuesday. has anyone done it yet?

Original post by jmsk_

Anyone doing it this year?

I did it today :smile:

I won’t give hints and obviously I don’t know how I did yet but I found it easier than a lot of the past papers I looked at (although I didn’t do much preparation for it tbh).

Good luck!

Cambridge Chemistry Challenge Lower Sixth!

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