OCR Chemistry A F322 Chains, Energy and Resources Wed 23 May 2012

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Original post by Stir fried Giblets

Thought it was going well, then I started doing a past paper so: **** :tongue:

I know the feeling! But exam papers are the best way to boost your grade. I currently have 15 or so sitting on my desk that I'm hoping to complete by the end of this week XD

Reply 41

Stir fried Giblets

Original post by mmasters

I know the feeling! But exam papers are the best way to boost your grade. I currently have 15 or so sitting on my desk that I'm hoping to complete by the end of this week XD

Tried it, then went up by 10 marks but still didn't go up a grade :frown:

FML.

Reply 42

03zara

Hi do you guys know where i could get the revision notes that goes with the specification?

Reply 43

bencwbrown

Hi everyone, I have made some past paper booklets on the topics in this unit, if anyone would like to have a collection that they could go through or focus on a specific topic :smile:

If you want a booklet on a more specific topic than the ones I've uploaded (as they may be a bit broad still) then don't hesitate to ask and I can make one. (I converted some to pdf to make the file small enough to upload in one piece)

Alcohols and Halogenoalkanes Scheme.rtf621.5KB

Rates and Equilibrium Scheme.rtf267.1KB

Energy.rtf396.0KB

Energy Schemes.rtf222.4KB

Basic Concepts and Hydrocarbons.pdf271.7KB

Basic Concepts and Hydrocarbons Scheme.pdf311.2KB

Analysis.pdf211.2KB

Analysis Scheme.rtf172.7KB

Alcohols and Halogenoalkanes.rtf656.0KB

Rates and Equilibrium.rtf321.2KB

Reply 44

bencwbrown

Couldn't fit them all into 1 post

Resources.rtf105.2KB

Resources Scheme.rtf72.8KB

Reply 45

Patchey1000

Original post by browb003

Hi everyone, I have made some past paper booklets on the topics in this unit, if anyone would like to have a collection that they could go through or focus on a specific topic :smile:

Nice good job I've been Savin up my printer credits to use on something like this

Reply 46

Stir fried Giblets

Original post by browb003

Hi everyone, I have made some past paper booklets on the topics in this unit, if anyone would like to have a collection that they could go through or focus on a specific topic :smile:

You are awesome

Reply 47

Poffertje

Hey,

Could somebody help me with Dynamic equilibrium and just the basic concepts that maybe go with it? I kinda struggle a lot on them sort of Q's on past papers - did the Jan 2012 mock this week and I probably spent like 10 minutes or so on the Q in there!
I do sometimes understand it, I just get confused with all the effects temperature and pressure will have on equilibrium.
Thanks! :smile:

Reply 48

adamcusirinzon

Original post by Myda

A good idea would just be to learn using the mark-schemes rather than using the book, it tends to waffle sometimes and mentions points which arent accepted in the mark scheme thus over-complicating things and wasting your time.

Reply 49

ofudge

From what I've found, this exam is very attention to detail.
Make sure you state where your double bond is... make sure you cover every point in the statement, and learn your definitions! Every year at least two have come up. The definitions that you need to know are:

Enthalpy Change of Reaction: The enthalpy change expressed in the molar quantities in a equation, with all reactants and products being in their standard states under standard conditions.

Enthalpy Change of Combustion: The enthalpy change that takes place when 1 mole of compound COMBUSTS (NOT BURNS) completely with oxygen under standard conditions, all reactants and products being in their standard states.

The Enthalpy Change of Formation: The enthalpy change that takes place when 1 mole of compound is formed from its constituent elements under standard conditions, all reactants and products being in their standard states.

Radical- Species with an unpaired electron
Electrophile- Electron pair acceptor
Nucleophile- Electron Pair Donor
Average Bond Enthalpy- The enthalpy change required to break by homolytic fission 1 mole of a given gaseous species.
Activation Energy- The minimum amount of energy required for the bonds to break in a reaction and for them to collide and react together.

Le Chatelieur Principle: For a reaction in Dynamic Equillibrium, if a change is made to the conditions (Pressure, Concentration, Temperature), the equillibrium will act in such a way to minimise this change

Functional Group- An atom/group of atoms responsible for the chemical properties of the compound and its reactions

Homologous Series: Group of Organic Molecules with the same functional group and each successive member differing by CH2

Empirical Formula: The simplest whole number ratio of atoms of each element present in a compound.

Molecular Formula: The actual number of atoms of each element present in a compound

Displayed Formula: Shows the atoms in a compound and the bonds located between them.

Skeletal Formula- Shows the minimal detail of a compound, by removing any additional atoms leaving only the carbon skeleton and any associated functional groups

Any More i've missed be sure to add them up :biggrin:

good luck everyone :smile:

Reply 50

mmasters

This exam is consuming my life. I had a dream that a carbon atom and four hydrogen atoms (methane) were holding hands and dancing towards a chlorine radical. Then one of the hydrogen atoms let go of the carbon atom and began to hold hands with the chlorine radical. Now I don't think I'll ever forget that radical substitution mechanism.

Reply 51

mmasters

Sorry to be an over poster guys. But I saw this on the examiners report and it brought joy to my life. So, I thought I'd share knowing that we're all on the brink of insanity with these mother loving exams and could do with a communal laugh :biggrin:

Reply 52

thescientist17

I'm SO scared for this exam! I got an A in F321 (but only just) and I'm predicted an A overall but you need about 80% in this module! I'd be so happy even if I just managed to scrape an A but I'm finding this hard.

I know it's tricky explaining these sorts of things on here but I don't understand structural formula, like what do the brackets mean? How do you show a branch? Do you go by the longest chain and work from that?

Reply 53

blue012

Could anyone please help with E/Z isomerism. How do you know that your hydrocarbon can form this and do they always have to be functional groups of the double bonded carbon. ASAP PLS>

Reply 54

Rough Silk

Original post by blue012

Could anyone please help with E/Z isomerism. How do you know that your hydrocarbon can form this and do they always have to be functional groups of the double bonded carbon. ASAP PLS>

Only Alkenes can have E/Z isomerisation.

E is when groups are bonded to opposite sides of the double bond.
Z is when they bond to the same side.

Any question on this make sure you say CARBON CARBON double bond that CANNOT ROTATE.

Hope this helps :smile:

... Also, does anyone know what kind of raw mark is needed for 100% UMS?

Thanks :smile:

Reply 55

myyrh

Original post by JohnSimmons

... Also, does anyone know what kind of raw mark is needed for 100% UMS?

Thanks :smile:

It's impossible to say because the grade boundaries fluctuate so much. I would probably say that you'd be looking at around the 95+/100 mark for full UMS normally.

Reply 56

adamcusirinzon

Original post by thescientist17

I dont think you need 80% for an A. Majority of papers I have seen, for the summer exams anyway, have requires 75-77% raw marks....anyone want to add me on facebook/msn and we can test each other and give pointers and how to improve answers/make them more concise. My fb name is the same as my name on here

Reply 57

Poffertje

Original post by adamcusirinzon

Yeah I'm starting to see that now! Thanks for the advice.
You mentioned msn/fb, I wouldn't mind doing it!

Reply 58

Alotties

I am dreading this exam!
I feel like I know nearly everything then I look at a paper and struggle with some questions.
We haven't even covered esters yet in my class :frown:

Reply 59

thescientist17