Edexcel IAL, Unit 4: Rates, Equilibria and Further Organic Chemistry. 14-Jun-2016

This is the official thread for June 2016 Edexcel exam IAL, Unit 4 Chem.

Post all your doubts here. (^.^)
Half of Jan is done, so we only got 4 more months left, hope the prep is going well.

Reply 1

therecovery

OP

5

Bump.

Posted from TSR Mobile

Reply 2

imsuffering

Right help me lads

Srs business right here

Why are halogenoalkanes good solvents for oil and grease?? :confused:

(edited 8 years ago)

Reply 3

Ayman!

15

subbing. Unit 4 is nice, Unit 5... not so much.

Reply 4

MeeraP07

7

*IMPORTANT*Hi everyone! I'm actually in my first year of university now but thought I would post all of my resources from my A levels last year. There are 1000s of resources including notes, practice questions and answers etc. for A2 Biology, Chemistry and Maths. There were far too many to upload them individually so I uploaded them to a google drive so if you follow the link below it will take you to them! I found TSR so helpful when I was doing my A Levels and found other peoples notes to be useful so I thought I would reciprocate the favour and upload mine! They aren't exam board specific so I hope they're helpful (although I did do OCR-Bio, Edexcel- Chem and Maths).Enjoy!https://drive.google.com/folderview?id=0B5eZEYkqM9hmUTFod25kMm1WN28&usp=sharing

Reply 5

therecovery

OP

5

Original post by MeeraP07

*IMPORTANT*Hi everyone! I'm actually in my first year of university now but thought I would post all of my resources from my A levels last year. There are 1000s of resources including notes, practice questions and answers etc. for A2 Biology, Chemistry and Maths. There were far too many to upload them individually so I uploaded them to a google drive so if you follow the link below it will take you to them! I found TSR so helpful when I was doing my A Levels and found other peoples notes to be useful so I thought I would reciprocate the favour and upload mine! They aren't exam board specific so I hope they're helpful (although I did do OCR-Bio, Edexcel- Chem and Maths).Enjoy!https://drive.google.com/folderview?id=0B5eZEYkqM9hmUTFod25kMm1WN28&usp=sharing

thank you so much :smile:

really appreciate it

Reply 6

therecovery

OP

5

Original post by imsuffering

Right help me lads

Srs business right here

Why are halogenoalkanes good solvents for oil and grease?? :confused:

from my knowledge, its because haloalkanes are non polar. its only the C - X part where X can be a halogen which is polar. In long chain haloalkanes, the hydrophobic R group (ch3,ch2,ch2..) is much bigger than the polar C-X bond. therefore, the molecule is mostly non polar. oil and grease are nonpolar as well. hence, haloalkanes can be dissolved in oil and grease and vice versa as non polar interactions can be formed.

Reply 7

Mehodax

2

Original post by therecovery

from my knowledge, its because haloalkanes are non polar. its only the C - X part where X can be a halogen which is polar. In long chain haloalkanes, the hydrophobic R group (ch3,ch2,ch2..) is much bigger than the polar C-X bond. therefore, the molecule is mostly non polar. oil and grease are nonpolar as well. hence, haloalkanes can be dissolved in oil and grease and vice versa as non polar interactions can be formed.

I think this answers your question properly @iamsuffering

Reply 8

O$car

2

hey can anyone help me with question 11d from 2013JUN paper 4R, it is very HARD

Reply 9

sonam_28

1

how many peaks are there in a low resolution nmr spectrum for pentanal?

Reply 10

Mehodax

2

Original post by sonam_28

how many peaks are there in a low resolution nmr spectrum for pentanal?

Five peaks as there are five hydrogen environments

Reply 11

O$car

2

does any know how to solve questions regarding experimental errors, like take me through your thought processes

Reply 12

Julia3

9

If the question asks for the % experimental error for a piece of apparatus, you do:

percentage error for the apparatus / measurement made on apparatus x100

For example, the % error for a burette is +/- 0.2cm^2
You measure 26cm^2
The % error for the burette reading is:
(0.2/26) x 100 = 0.77%