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AQA A-Level Chemistry Paper 2 (7405/2) - 19th June 2023 [Exam Chat]

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I see what you mean but there was also a reaction underneath it with a ketone, it has the same number of carbons and hydrogens as the first one but it had the formula:

CH3COCH2CH3 + 2H2 --> CH3CH(OH)CH2CH3

The hydrogens don't balance here so I'm still confused but thank you for the answer

https://www.vedantu.com/seo/content-images/1dc83d68-cda4-441a-afd3-a267213d7bc3.png

https://ibb.co/fdVbMJf

[H] means hydrogen from a reducing agent (NABH4 for example)

Reply 61

username5843686

hardest paper 2 guys ?

Reply 62

.SBH

Original post by DH.5000000

Anyone have any predictions?

Amount of substance
Le Chatelliers
Energetics
Kinetics
Rate equations
Mechanisms for organic + reagents
NMR
Chromatography

PRACTICALS
Distillation of alcohols
Tests for alcohols, aldehydes, alkanes + COOH
Crystallisation

Reply 63

.SBH

Original post by Atif Siddique

https://www.vedantu.com/seo/content-images/1dc83d68-cda4-441a-afd3-a267213d7bc3.png

https://ibb.co/fdVbMJf

[H] means hydrogen from a reducing agent (NABH4 for example)

Thanks but why is the ketone one I mentioned above 2H2 and not H2? Or should the one I mentioned be H2 instead of 2H2

(edited 10 months ago)

Reply 64

Sb17890

hi , any chance you could send or upload the whole document . im struggling with all the conditions and reagent and it would really help

Original post by .SBH

KCN in ethanol/water mixture and heat under reflux

Reply 65

.SBH

Original post by Sb17890

hi , any chance you could send or upload the whole document . im struggling with all the conditions and reagent and it would really help

Sure

aqa-mechanisms-a-level-summary.pdf163.8KB

Reply 66

Atif Siddique

Original post by .SBH

Thanks but why is the ketone one I mentioned above 2H2 and not H2? Or should the one I mentioned be H2 instead of 2H2

should be h2

Reply 67

.SBH

Original post by Atif Siddique

should be h2

Ok thank you 😊

Reply 68

maaz_2479

nice, is there any reason why you think these topics will come up?

Original post by .SBH

Reply 69

CharlieB8KR

Original post by maaz_2479

nice, is there any reason why you think these topics will come up?

im pretty sure thats just most of the spec and the most common topics that come up in detail
organic is very similar every year so you do kinda just have to revise everything as every topic links

Reply 70

rizzy0la

Based on 2022 paper/ looking at previous 6 markers from all past papers
- Definitions
- Graph questions (either having to work out rates/ but i feel like drawing the graph for arrhenius will come up)
- Practical terminology (why we do this... how we can improve experimental procedure blah blah)
1.3 Bonding and physical properties for physical
1.5 kinetics and Maxwell B explain or draw on graph new temp
1.9 rate equations will come up + rate determining step
1.6 Expect Kc (none on p1)
1.6 q=mcT calc. or 1.2 ideal gas equation calc pV=nRT (or both who tf knows)

3.3 Ozone depletion and cfcs
3.2Free radical SUBS
3.13 Zwitterions
3.13 DNA structure
3.5/3.9 Learn biofuels/biodiesel
3.4 Cracking and combustion of alkanes.
3.10 Benzene stability
3.16 Chromatography!!!
3.12 Named polymer types (kevlar, nylon 66 eg)
3.1/3.7 Isomerism (structural/ optical and geometric).
Fractional distill apparatus/ reflux
Empirical and MF

6markers:
Organic analysis and global warming
Aromatics
Making aspirin
Polymers and their biodegradability?
TLC practical
Carbon NMR

Original post by DH.5000000

Anyone have any predictions?

(edited 10 months ago)

Reply 71

Greatdogs2005

how should I revise practicals?
and what practicals are in paper 2?

Reply 72

FloryK

can someone help i dont get why he put the O and CH3 on the left hand side like i get why he did C doubke bond O and all the stuff on the right side but what is going on at the left of the molecule??

Reply 73

CharlieB8KR

Original post by FloryK

can someone help i dont get why he put the O and CH3 on the left hand side like i get why he did C doubke bond O and all the stuff on the right side but what is going on at the left of the molecule??

i assume its simply because no other info is provided and the question explicitly says it is an ester so he added the CH3-O- to form the ester as this must be the structure based off of the rest of the information provided

Reply 74

rizzy0la

Original post by Greatdogs2005

how should I revise practicals?
and what practicals are in paper 2?

To revise id say going through past papers w questions to do with practical terminology (why do we stir this/ rinse burette or what issues are caused by leaving the funnel in) and learn the generic answers for them.
Also definitely learn how to draw all apparatus set ups as they like to ask. (Reflux set up/ distillation/ filtration methods and be able to label)!
Example:
Explain why enthalpy value is less than according to book = poor/ no insulation so heat loss to surroundings.
Suggest an improvement: Add a lid/ polystyrene cup.

Physical
1 Make up a volumetric solution
2 Measurement of an enthalpy change
3 Investigation of how the rate of a reaction changes with temperature
7 Measuring the rate of reaction:
by an initial rate method
by a continuous monitoring method

Organic
5 Distillation of a product from a reaction
6 Tests for alcohol, aldehyde, alkene and carboxylic acid
10 Preparation of:
a pure organic solid and test of its purity (aspirin)
a pure organic liquid (cant remember but i think this one is making esters)
12 Separation of species by thin-layer chromatography

(edited 10 months ago)

Reply 75

ShamBlade

NMR and mass spec defo likely to come up