[Amz1217]

(Original post by gloomyrainbow)
Hi guys

Any ideas about what you think might come up in this paper.
I personally think that those big questions that normally come towards the end of the paper where you have to analyse the i.r and mass spec and mr/empircal formuale and deduce the compound is going to come up, becuase it didnt come up in jan 2012.

what do you guys think?

I think there will be some stuff on resources (module 4 from the OCR Heineman book) coz that was absent from Jan

[thepastpaper]

atm im gonna fail this test yeah dont get how to draw isomers

[Dreamweaver]

(Original post by gloomyrainbow)
Hi guys

Any ideas about what you think might come up in this paper.
I personally think that those big questions that normally come towards the end of the paper where you have to analyse the i.r and mass spec and mr/empircal formuale and deduce the compound is going to come up, becuase it didnt come up in jan 2012.

what do you guys think?

Halogenalkanes are very likely to come up. Bond polarity vs bond enthalpies, how to determine relative rates etc..

[needtosucceed=)]

(Original post by Amz1217)
I think there will be some stuff on resources (module 4 from the OCR Heineman book) coz that was absent from Jan

totally agree, there was hardly anything on resources in january! better start revising it LOL

[needtosucceed=)]

(Original post by gloomyrainbow)
Hi guys

Any ideas about what you think might come up in this paper.
I personally think that those big questions that normally come towards the end of the paper where you have to analyse the i.r and mass spec and mr/empircal formuale and deduce the compound is going to come up, becuase it didnt come up in jan 2012.

what do you guys think?

there were about 10 marks for ir and mass spec in january..

[Myda]

(Original post by thepastpaper)
atm im gonna fail this test yeah dont get how to draw isomers

Well, think about it this way: you can split isomers into 2 groups, structural isomers and stereoisomers. Stereoisomers will only work with a double bond present, so you only have to worry about mainly alkenes there, unless you get a stupidly complicated one ofc And then, within structural you can have 3 ways of doing it. You can have chain, simplest one where you change length of chain, so butane for example could instead become 2-methylpropane because you move one of the C off the longest chain and attach it elsewhere, in this case on the second C. If you have functional groups such as OH present, you can get isomers by placing it at different positions on carbon chain (hence the name 'positional isomer') and then the third one is functional I think? Something about changing the functional group altogether, I use this last but if you have an OH group I think you are allowed to split that up so you can maybe get a c=o group somewhere instead.

Right, hope that quite long explanation helped!

[dellprinter]

(Original post by adamcusirinzon)
are you the guy I ignored when you added me ? and no, just being nice and helping other people out...it's called being human, you should try it sometimes

no?
but i dont know why youd put ur facebook and email open for all on the internet

[thepastpaper]

(Original post by Myda)
Well, think about it this way: you can split isomers into 2 groups, structural isomers and stereoisomers. Stereoisomers will only work with a double bond present, so you only have to worry about mainly alkenes there, unless you get a stupidly complicated one ofc And then, within structural you can have 3 ways of doing it. You can have chain, simplest one where you change length of chain, so butane for example could instead become 2-methylpropane because you move one of the C off the longest chain and attach it elsewhere, in this case on the second C. If you have functional groups such as OH present, you can get isomers by placing it at different positions on carbon chain (hence the name 'positional isomer') and then the third one is functional I think? Something about changing the functional group altogether, I use this last but if you have an OH group I think you are allowed to split that up so you can maybe get a c=o group somewhere instead.

Right, hope that quite long explanation helped!

Thank you so much i think it will be clearer when i try out some past papers. are you doing this exam as well? good luck

[geditor]

Hi, so how do you guys revise? Got any tips or good revision techniques?

[Fatima0065]

(Original post by needtosucceed=))
totally agree, there was hardly anything on resources in january! better start revising it LOL

What do you need to revise on resources??

[Mehalan]

does anyone have the jan 2012 paper for this unit, i am currently revising for this exam next week so i just want to look at the january paper before i go into the exam. Mark scheme with the paper would be nice thanks

[geditor]

what do we need to know about catalytic cracking? I can only find one thing in the book about it, zeolite?

[Stir fried Giblets]

(Original post by geditor)
what do we need to know about catalytic cracking? I can only find one thing in the book about it, zeolite?

It requires a high temperature (about 450 degrees I think, but you don't have to specifically know that) and a zeolite catalyst also that cracking breaks long carbon chains into a mixture of alkanes and alkenes.

[Bubbles2109]

(Original post by Mehalan)
does anyone have the jan 2012 paper for this unit, i am currently revising for this exam next week so i just want to look at the january paper before i go into the exam. Mark scheme with the paper would be nice thanks

Here you go

[Fatima0065]

Can anyone sum up what we need to know for pg 232 of the OCR text book and likely examination questions on that page and the following page too please thankyou

[Ashfak786]

Help needed please! i do not understand question 3) the answer is 5.68 × 107 please tell me how you get there

1) An important reaction in the manufacture of nitric acid is the catalytic oxidation of ammonia.

4NH3 (g) + 5O2 (g) --> 4NO (g) + 6 H2O (g) delta H = - 909 kj mol-1
<--

low pressures and low temperatures would give the maximum equilibrium yield of NO
explain why?


2) The actual conditions used in the catalytic oxidation of ammonia include 900 degrees C and an increase in pressure

Suggest why these conditions are a compromise.


3) A factory makes 2.50 x 10 (to the power 5) mol of NO a day. How much energy is released every day?


suggest how this energy can be used to reduce the cost of making NO.

[Speedo]

2.50x10^5 x 909KJ, then divide by 4, because in the equation it states that 4mols of NO are made

[Ashfak786]

(Original post by Speedo)
2.50x10^5 x 909KJ, then divide by 4, because in the equation it states that 4mols of NO are made

thank you very much got really confused with that

[narli]

(Original post by Fatima0065)
Can anyone sum up what we need to know for pg 232 of the OCR text book and likely examination questions on that page and the following page too please thankyou

everything on resources..
you should know about the greenhouse gases, about ozone, about catalyic conveters and green chem

[georgem93]

(Original post by geditor)
what do we need to know about catalytic cracking? I can only find one thing in the book about it, zeolite?

Remember sometimes the examiners are fussy and want you to say thermal decomposition instead of cracking.