OCR CHEMISTRY (F324) - June 2011 Exam.

1,
a,
i, State the reagents and conditions neccesary to form 1 mole of chlorobenzene from two toothpicks and a paperclip.

ii, what are the ethical implications of using paper clips over stapels?

Hahahah

and
Outline the formation of mouth wash from phenol [8 marks]

Reply 61

Julian_valensi

6

Original post by Rosi M

Hahahah

and
Outline the formation of mouth wash from phenol [8 marks]

lol,

on a more serious note, no ones solved forming CH3CH2COOCH(CH3)2, from propene yet, get stuck in it uses AS knowledge aswell, chuffin great chem right there!

Reply 62

Sereni

14

Original post by Freerider101

I agree with you. I've always stuck to the specification exactly and its worked out for me. I've found OCR Chemistry to set fair papers, OCR Maths on the other hand....

Yea, I found the paper hard, but in no way was in unfair, tight for time etc yea, but it tested the specification quite well I thought. Like the 'unfair' magic tang question all you had to do was use your knowledge of pKa and pH and your knowledge of buffer solutions and it was actually a rather easy question, and the last mark was just for a basic understanding of what is actually happening (for example low pH linked to sour taste) and will probs be AVP. I might ask my tutor what the ratio for lactic acid to salt was at some point, or I may just enter a haze of drunkeness till results day after next monday.

That wasnt even my point though, even if it was a paper that tested the pH of a magical fairy solution and asked how you could use this solution to take over the world and the ethical implications of doing so it is in that past. We have to assume that the resit will be on the specification and prepare to be tested on the specification and around the specification, because at least if you prepared well for it you can say that you tried your hardest, as opposed to missing the grade because you were sulking from a different exam

Reply 63

Jtking3000

13

My guess for one of the questions:

"A company wants to make a chemical that will clean teeth to give them a 'sparkle ting'. Chemists have identified a chemical that will do just this, the NMR spectrum is shown below. Work out the structural formula of this chemical. Comment on this validity that the chemical with give a magic 'sparkle ting'
[10]"

Reply 64

LauraBritton

Original post by sam.parsons

All the papers and Markschemes i have - hope it helps :smile:

Thanks so much for the jan 2011 paper, I've been searching for it everywhere!!! x

Reply 65

percy93

Original post by Julian_valensi

1,
a,
i, State the reagents and conditions neccesary to form 1 mole of chlorobenzene from two toothpicks and a paperclip.

ii, what are the ethical implications of using paper clips over stapels?

Mix the two toothpicks and the paperclip with magic tang and reflux for 24 hours

Reply 66

student777

8

Original post by Julian_valensi

I can see why ive made this confusing, it isnt really 'propyl propanoate', its essentially, propyl-2-propanoate, the esters formed form a secondary alcohol and a carboxylic acid.

Surely if you hydrate propene you will get both propan-1-ol and propan-2-ol?

On another note, please can everyone stop going on about the F325 paper. It's getting ****ing annoying, we've done it now so let it go.

(edited 12 years ago)

Reply 67

Julian_valensi

6

Original post by student777

Surely if you hydrate propene you will get both propan-1-ol and propan-2-ol?

On another note, please can everyone stop going on about the F325 paper. It's getting ****ing annoying, we've done it now so let it go.

nope, it will only form a secondary alcohol due to protons being attracted to the carbon bonded to more protons(the CH2, not CH) (to be fair that isnt present in anyway in the OCR Chem A spec. so i shoudnt have included it, i should really apply for a job writing papers)

Try adding HBr, see what you get then.

oh and dont seperate any prodcuts, it can be done with 1 sample.

(edited 12 years ago)

Reply 68

Fifi93

Any predictions of topics that may come up?? I'm trying to focus on specific topics that I need to revise.

Reply 69

Rosi M

11

Original post by Fifi93

Any predictions of topics that may come up?? I'm trying to focus on specific topics that I need to revise.

I have a feeling all the zwitterion stuff may come in. Hope it does!

Any predictions for the mechanisms? Jan '11 had nucleophilic addition and nitration of benzene and a 6 marker on condensation to make polyesters i THINK.

Reply 70

Fifi93

Original post by Rosi M

I have a feeling all the zwitterion stuff may come in. Hope it does!

Any predictions for the mechanisms? Jan '11 had nucleophilic addition and nitration of benzene and a 6 marker on condensation to make polyesters i THINK.

Ummm, the reduction with NaBH4 has come up before (jan 10). The nitration of benzene seems to come up regularly so don't leave it out. Maybe chlorination or bromination of benzene will come up.

TIP: Just revise all the mechanisms if u can. :smile:

Reply 71

Freerider101

12

Original post by Rosi M

I have a feeling all the zwitterion stuff may come in. Hope it does!

Any predictions for the mechanisms? Jan '11 had nucleophilic addition and nitration of benzene and a 6 marker on condensation to make polyesters i THINK.

Aren't those the only 3 mechanisms we need to know anyway?

Reply 72

Freerider101

12

Original post by Rosi M

Hahahah

and
Outline the formation of mouth wash from phenol [8 marks]

Use a 1 molar solution

Reply 73

percy93

Original post by student777

Good answer.
Tip: a good word to use is 'stereoselectivity' when talking about producing isomers from enzymes etc.

gotcha. thanks dude

Reply 74

Carpet21

12

Original post by Ayostunner

Got a D in jan...need over 72 ums to get a B overall for uni

Fml ...i havent even started revising yet

I need near enough full marks to get my A for uni after that horrific excuse for an exam last Wednesday, so I feel your pain!

Reply 75

percy93

Original post by Rosi M

I have a feeling all the zwitterion stuff may come in. Hope it does!

Any predictions for the mechanisms? Jan '11 had nucleophilic addition and nitration of benzene and a 6 marker on condensation to make polyesters i THINK.

i'm hoping lot's of module 1 and maybe a bit of NMR... but no module 2 or magic tang!

Reply 76

percy93

Original post by Carpet21

I need near enough full marks to get my A for uni after that horrific excuse for an exam last Wednesday, so I feel your pain!

yeh same, I'm aiming for a B.. got an A in AS but felt i got a C last wed, got a C in the coursework... not sure how well i have todo to get a B overall through this exam....

Reply 77

Killmepls

10

Can someone explain the worked example 2 on page 96 bottom left, I don't understand how you can distinguish between the two esters and they haven't explained it at all..

Reply 78

Carpet21

12

Original post by Killmepls

Can someone explain the worked example 2 on page 96 bottom left, I don't understand how you can distinguish between the two esters and they haven't explained it at all..