[3raindrops]

I'm really nervous about this, its the chunkiest part and really not keen on the whole ozone thing. I've got about 3 days to revise for this, C2, and Biology so its going to be tight.

This is the make it or break it paper, for both AS and A2, because the percentage is high (50%)

fingers crossed now!

[JsConcernedMum]

(Original post by abzy1234)
I would advise him to go over his notes thoroughly now, as you said there's not enough time now. Tell him to spend more time over the topics he's not too sure about, ensuring he understands the content fully.

Also start on the past papers. These are really important, and helps you to understand how the exam will be laid out; what the examiners expect, and how your son should structure your answers.

Like you said, the mark schemes are very specific; so tell your son after doing the past paper, to really look closely at the mark scheme and mark his work strictly according to it. Make sure he doesn't repeat his mistakes throughout the past papers.

Other than that, how much support has the school given him for the pre-release material? Tell him to go through this, and ensure that he fully knows the content of this booklet.

Good luck

(Original post by chrisduck)
I would agree with everything said above. But also after marking the past papers he should write out an example answer from the mark scheme if he got it completely wrong. You mentioned that he struggles with specifics, as Salters and OCR love specifics he would probably benefit from reading the examiners reports with the past papers after marking them. I do that and it helps you get a good sense on what they want in each question, especially the long ones...

Even though there is not much time left if you don't already have it buy the CGP salter B chemistry revision guide and tell him to read it throughly ( a few times) and then just past papers and more pastpapers.

Maybe let your son have they days off school to revise (and nothing else :P ) it would probably make a huge difference in his grade(s).

Hope it goes well!

(Original post by SimpleGirl)
I agree with this. It's good advice, imo
Hope he does well

Thanks to everyone who replied - some great advice there. We have CGP and I'm seriously considering keeping him off next week apart from exams. I assume the examiners reports are on the website somewhere, so I'll look for those too.

Thanks again. Fingers crossed! Good luck to all of you too.

[Zhy]

(Original post by JsConcernedMum)
Thanks to everyone who replied - some great advice there. We have CGP and I'm seriously considering keeping him off next week apart from exams. I assume the examiners reports are on the website somewhere, so I'll look for those too.

Thanks again. Fingers crossed! Good luck to all of you too.

Just tell them he's ill, it worked for me. I talked to my parents and they're aware that I have almost 20 A-level exams, and now I don't go to my lessons because I can just start working at 9 AM to 9 PM revising what I need to be learning (especially as sometimes teachers have "revision lessons" which revise topics that we're already comfortable with!). Just be careful that he does spend the time working, because it's really easy just to get stuck surfing the internet and end up not using the time productively. But a lot of people do this... there's a reason attendances are so low around exam time.

[Salmonidae]

(Original post by Vorex)
My teacher's done some analysis of the pre-release booklet, so I thought I'd share some of the possible questions/topics that any my teacher think could come up.

- PPM -> % conversions
- Knowledge on Ziegler-Natla catalysts (in Storylines p98-100)
- Polymerisation reaction equations
- Intermolecular forces explanation i.e. why does HDPE has a higher boiling point than LDPE (Properties & Structures of LDPE & HDPE)
- There could possibly be a bond enthalpy question on a -O-O- (organic peroxide) e.g. How much energy would be required to break one molecule? Or to work out the frequency needed to break it, vice versa.
- Talking about homolytic fission, maybe an explanation?
- Free-radical initiation of polymerisation with R-O-O-R' molecules
- Propagation & Termination question
- E/Z isomerism question
- There could well be questions on 'gutta-percha' molecules (p105 story), like draw the skeletal formula or draw the full structural formula (from a skeletal formula) and also naming the molecule questions.
- Make sure also you're comfortable with all the homologous series. There could well be a question about the first page about naming functional groups, something basic like that

Hope this was maybe of some help. I'll probably come up with some possible questions on the weekend and post them on here if you'd like

Just to bring this back to the forefront, this stuff is solid gold and easy marks

[JsConcernedMum]

(Original post by RebeccaTenney)
http://www.scribd.com/doc/91989461/F...s-from-the-sea

http://www.scribd.com/doc/92674917/F...mer-revolution

http://www.scribd.com/doc/93118514/F...the-atmosphere

i made these notes and i got 95% on the mock, hope that they help and good luck!

These are great, thanks, but something caught my eye. Hope this doesn't sound rude (and I may be wrong as I didn't study chemistry and it could just be one teacher's view) but you mention E/Z isomer differences as whether they have groups on opposite or same side of double bond. My son lost the mark ("too vague") for this in his mock for using the word side. Apparently he should have referred to the groups on each carbon of the double bond. Thought I'd mention it ... just in case

[winningjojo]

Question: The displacement reactions for the halogens. Could someone please tell me what they are for Cl2 +KBr, Cl2+KI, Br2+KI. Plus the colours of the two layers formed from each of these when a cyclohexane is added. The Chemical Ideas doesn't seem to have it very clear neither and the revision guide doesn't seem to state it. So wondered if you guys could help. Thanks in advance. ... Shift+R improves the quality of this image. CTRL+F5 reloads the whole page.

[winningjojo]

and i don' know why the straneg Crtl+f5 thing came up. wierd :O

[winningjojo]

(Original post by Zhy)
Just tell them he's ill, it worked for me. I talked to my parents and they're aware that I have almost 20 A-level exams, and now I don't go to my lessons because I can just start working at 9 AM to 9 PM revising what I need to be learning (especially as sometimes teachers have "revision lessons" which revise topics that we're already comfortable with!). Just be careful that he does spend the time working, because it's really easy just to get stuck surfing the internet and end up not using the time productively. But a lot of people do this... there's a reason attendances are so low around exam time.

we're lucky. our school gives all year 12's two weeks study leave around the time of most exams.

[winningjojo]

(Original post by JsConcernedMum)
Thanks to everyone who replied - some great advice there. We have CGP and I'm seriously considering keeping him off next week apart from exams. I assume the examiners reports are on the website somewhere, so I'll look for those too.

Thanks again. Fingers crossed! Good luck to all of you too.

officialSalters chemistry guide is FANTASTIC. I know its just a week to the exam but it REALLY helps puts all the content from the Chemical Ideas into an easy to manage sections+questions at the end of each page + exam questions too and hints and tips of whatt they want in the exam. get it

[RebeccaTenney]

(Original post by JsConcernedMum)
These are great, thanks, but something caught my eye. Hope this doesn't sound rude (and I may be wrong as I didn't study chemistry and it could just be one teacher's view) but you mention E/Z isomer differences as whether they have groups on opposite or same side of double bond. My son lost the mark ("too vague") for this in his mock for using the word side. Apparently he should have referred to the groups on each carbon of the double bond. Thought I'd mention it ... just in case

I saw that when i was doing past papers, but you are entirely right my teacher told me to say this instead: there must be two different atoms (or groups of atoms) on each carbon atom involved in the double bond. But thank you for letting me know!

[Salmonidae]

(Original post by winningjojo)
Question: The displacement reactions for the halogens. Could someone please tell me what they are for Cl2 +KBr, Cl2+KI, Br2+KI. Plus the colours of the two layers formed from each of these when a cyclohexane is added. The Chemical Ideas doesn't seem to have it very clear neither and the revision guide doesn't seem to state it. So wondered if you guys could help. Thanks in advance. ... Shift+R improves the quality of this image. CTRL+F5 reloads the whole page.

Hey!

OK so the way displacement reactions work when it comes to the halogens is that the higher up elements displace the lower down ones. This is because the higher up elements are better oxidising agents, therefore they oxidise the other halogen and essentially 'steal' their electrons, becoming reduced themselves.

So in the case of your reactions:

Cl₂ + 2KBr ---> Br₂ + 2KCl This is because Cl is a better oxidising agent that Br so Br is oxidised and Cl is reduced, taking its place in the compound.

Cl₂ + 2KI ----> I₂ + 2KCL
Br₂ + 2KI ----> I₂ + 2KBr

Both these reactions work on the same principle.

Now as for colours in cyclohexane you just have to see which halogen is oxidised for it is this one which will dissolve in the cyclohexane.

Chlorine in cyclohexane is virtually colourless
Bromine in cyclohexane is an orange/red colour.
Iodine in cyclohexane is a pink/violet colour.


From this information you should be able to figure out that the first equation Bromine is oxidised, so the cyclohexane would be orange/red, and the 2nd and 3rd equations Iodine is oxidised so the cyclohexane would be pink/violet.


Hope this helps
S

[fallen_child]

what is the best advices to tackle this paper???

[3raindrops]

Can someone help me with the four types of bonding?

Hydrogen
Permanent dipole-permanent dipole
Permanent dipole-induced dipole
Induced dipole-Instantaneous dipole

[Salmonidae]

(Original post by 3raindrops)
Can someone help me with the four types of bonding?

Hydrogen
Permanent dipole-permanent dipole
Permanent dipole-induced dipole
Induced dipole-Instantaneous dipole

Hydrogen Bonds are a specific type of permanent dipole-permanent dipole bond where a delta-negatively charged Oxygen atom is attracted to a delta-positively charged Hydrogen atom (delta meaning small). Hydrogen is such a small atom that when these attractions form the distance between the hydrogen and the oxygen/nitrogen/fluorine atom (has to be one of those due to electronegative) it is covalently bonded to is almost the same as the distance between the hydrogen and the oxygen atom it is hydrogen bonded to. Therefore this type of intermolecular bond is exceptionally strong and we call it a hydrogen bond.

This diagram shows hydrogen bonding between water molecules


A permanent dipole-permanent dipole is formed exactly the same way as a hydrogen bond (i.e is the result of 2 polarised bonds) but can be with other atoms and is weaker due to bigger atoms involved and longer distances.

Here is a diagram showing permanent dipole-permanent dipole bonding in hydrogen chloride


Permanent dipole - induced dipole is where a polarised bond (lets stick with H-Cl from the diagram above) induces (i.e creates) a dipole on another molecule and is therefore attracted to it. The works because if a negatively charged atom, i.e Cl in H-Cl, approaches a neutral atom the negative charge will distort the electron cloud on the neutral atom and push away the electrons creating a positive charge there. Therefore there will now be a permanent dipole-induced dipole attraction.

Here is a diagram showing water (a permanent dipole) inducing a dipole in an O₂ molecule


Finally an instantaneous dipole - induced dipole works in exactly the same way as a permanent dipole - induced dipole except that instead of a permanent dipole there is an instantaneous dipole. These arise randomly in any molecule and are caused by the random movement of electrons creating an imbalance of charge which then induces a dipole in the molecule next door and forming an intermolecular bond. This is the weakest intermolecular force, and is also known as Van der Waals forces.

Final diagram showing instantaneous dipole - induced dipole


Hope this helps, ask if you're still unsure!

S

[misspinx20]

Hey i'm re-sitting this paper from last year, cause i got a C on it. But just be careful guys....know just about EVERYTHING...cause last year they asked some dodgy questions that we hadn't even learnt. Go through ALL the past papers, cause it does actually help! And i wouldn't worry much about the pre-release, cause theres only two pages dedicated towards it in the paper...they'd probably just ask to draw repeating units of polymers, compare hdpe and ldpe (specifically melting and boiling points), advantages and disadvantages of using poly(ethene). They might also ask to draw the intermolecular forces between two polymer chains....so know what type of bonding occurs where hope this would help! Good luck everyone!

[3raindrops]

(Original post by Salmonidae)
Hydrogen Bonds are a specific type of permanent dipole-permanent dipole bond where a delta-negatively charged Oxygen atom is attracted to a delta-positively charged Hydrogen atom (delta meaning small). Hydrogen is such a small atom that when these attractions form the distance between the hydrogen and the oxygen/nitrogen/fluorine atom (has to be one of those due to electronegative) it is covalently bonded to is almost the same as the distance between the hydrogen and the oxygen atom it is hydrogen bonded to. Therefore this type of intermolecular bond is exceptionally strong and we call it a hydrogen bond.

This diagram shows hydrogen bonding between water molecules


A permanent dipole-permanent dipole is formed exactly the same way as a hydrogen bond (i.e is the result of 2 polarised bonds) but can be with other atoms and is weaker due to bigger atoms involved and longer distances.

Here is a diagram showing permanent dipole-permanent dipole bonding in hydrogen chloride


Permanent dipole - induced dipole is where a polarised bond (lets stick with H-Cl from the diagram above) induces (i.e creates) a dipole on another molecule and is therefore attracted to it. The works because if a negatively charged atom, i.e Cl in H-Cl, approaches a neutral atom the negative charge will distort the electron cloud on the neutral atom and push away the electrons creating a positive charge there. Therefore there will now be a permanent dipole-induced dipole attraction.

Here is a diagram showing water (a permanent dipole) inducing a dipole in an O₂ molecule


Finally an instantaneous dipole - induced dipole works in exactly the same way as a permanent dipole - induced dipole except that instead of a permanent dipole there is an instantaneous dipole. These arise randomly in any molecule and are caused by the random movement of electrons creating an imbalance of charge which then induces a dipole in the molecule next door and forming an intermolecular bond. This is the weakest intermolecular force, and is also known as Van der Waals forces.

Final diagram showing instantaneous dipole - induced dipole


Hope this helps, ask if you're still unsure!

S

Thanks sooo much for that

thats seems to come up a lot and I never really learnt it properly. But you summarised it really well!

This was posted from The Student Room's Android App on my GT-I9100

[12sophie]

Does anyone have a link to the JAN 2012 past paper and mark scheme please? x

[totw]

For the advance notice article what do you need to know, because that is the one thing about this exam i am confused about?

[JsConcernedMum]

(Original post by 12sophie)
Does anyone have a link to the JAN 2012 past paper and mark scheme please? x

It's been posted somewhere earlier on this thread.

[Harantony]

(Original post by JsConcernedMum)
Sorry, concerned parent muscling in here, but hope you can help a bit please guys.

My son has literally just finished the course (last Friday) so not much real revision done as yet (Chemistry wasn't the only syllabus not finished! And he had three exams this week) He doesn't get study leave and has 4 other exams next week too, so time is veeeery short. Plus he has learning issues that slow him up!

He's hoping to do this to degree level so it's pretty important to him.

I've read the thread, but are there any other tips you can suggest to make sure he spends his little time wisely please?

Zhy's comments on mark scheme answers sound like a great idea - J's pretty good at Chemistry, but lacks precision in his written answers so tends to drop marks on longer answers. I don't suppose anyone has summarised these and could let me have a copy please?

Any other thoughts gratefully received.

Thanks

I would recommend looking at the specification:
http://www.ocr.org.uk/download/kd/oc...d_gce_spec.pdf

It's useful for long answer questions because it sometimes gives you exact answers they look for (e.g. global warming mechanism)