Chemistry OCR AS F321 Atoms, Bonds and Groups May 2012

[QUOTE=otrivine

I'm so jealous,my highlight of holiday was only getting taken shopping to meadow hall shopping centre since i have been ''revising and good'' lol.

Q: methylpropan1-ol and butan-1-ol are structual isomers, explain why methylpropan-1-ol has a lower boiling point (2mrks)

ICL has dipole-dipole forces though which have a higher relative strength than van der vaals forces, so that'd be the main reason wouldn't it?

Because methylpropan-1-ol has less contact surface point and there fore less van der waals forces

correct.

next question...

Under certain conditions propene can react to form alcohols,name reagents,conditions required & write a balanced equation and explain why it's possible to create 2 different products. (5marks)

correct.

next question...

Under certain conditions propene can react to form alcohols,name reagents,conditions required & write a balanced equation and explain why it's possible to create 2 different products. (5marks)

CH3CHCH2 + c2h5oH TO GIVE CH3CH2C=O-O-CH2-CH3 + H2O I can't balance from computer but is my equation right?
Conditions conc.h2so4 and heat under reflux . It is possible to create two products as it is symmetrical.

hey,
you got 2/5- I think I did not phrase the question right for you,sorry

your equation is correct and balanced but you reacted propene with ethanol= ethyl propanoate

You went wrong when reacting propene with an alcohol=ester ,instead of making propene into the 2 alcohols.

mark scheme
(Propene reacts with h20 to create alcohol)
CH2CHCH3+H20--->C3H7O7 = 1MARK

(naming possible 2 alcohols)
CH3CHOCH3 OR CH3CH2CH2OH=2 MARKS

and you got the 2 marks on the conditions=h2so4 + heat reflux =2marks

oh snap so gutted more please lool

It' kind of a good thing when mistakes are made and then you will remember next time

Next question..It's pretty meaty lol and good practice as it's worth 10 MARKS(almost a grade boundary)
9marks=answer
1mark=written communication

Describe the mechanism for the reaction between methane and bromine and explain why it is difficult to produce a single organic product.And include equations and conditions

But how should I draw the mechanism?

the mark scheme shows written equations, i have gave you a simple structure of answer

overall equation:
CH4+BR2 gives CH3BR +HBR
conditions:
U.V light
The intitaion:
BR2 gives two BR radicals
Propagation:
CH4+BR. gives CH3. +HBR
propagation:
CH3.+BR2 GIVES CH3BR+BR
termination
BR-BR to gvies BR2
type of fisision:
homolyitc fission
problem with this mechanism:
symmetrical, keeps reacting sue to radicals reacting non stop. cata;yic converters.
written communication

verall equation:
CH4+BR2 gives CH3BR +HBR*
conditions:
U.V light*
The intitaion:
BR2 gives two BR radicals
Propagation:
CH4+BR. gives CH3. +HBR
propagation:
CH3.+BR2 GIVES CH3BR+BR
termination
BR-BR to gvies BR2
type of fisision:
homolyitc fission
problem with this mechanism:
symmetrical, keeps reacting sue to radicals reacting non stop. cata;yic converters.*
written com

PERFECT
full marks

thank you shall i ask you now??? on unit 1 or 2?

unit 2

1)a compound with the same molecular formulae but a different structural formulae with a different arrangement of atoms.

2) The contain c=c bond which cannot rotate
And each C in the double bond must have 2 different functional groups attached to it.
-the contain cis isomers which have c=c with the 2 functional groups on the same side
trans isomers with the 2 substituent groups on different side

3)H+/cr2072- and h2so4

Excellent Answers

Yay.I thought that i wasnt going to get most of them...

have you got one more question i could answer.??
i need to get to sleep i have a revision resit class at 8.00

sure

1) How does a catalyst increase the rate of reaction (3)
2) Are alcohol soluble in water. Justify (2)