AQA exam Board Anyone have a PDF for the A level RP's for Biology AQA?

I am dong required practical 7, and I am trying to figure out what is in the chromatography solvent.

I have two solvents:

1:9 propanone to petroleum ether and

4:1:1 Butan-1-ol: Glacial acetic acid: Distilled water

If I recall there is also chromatography for amino acids, but I have only done A level OCR so it is a learning curve for me :)

Many thanks
 
I am dong required practical 7, and I am trying to figure out what is in the chromatography solvent.

I have two solvents:

1:9 propanone to petroleum ether and

4:1:1 Butan-1-ol: Glacial acetic acid: Distilled water

If I recall there is also chromatography for amino acids, but I have only done A level OCR so it is a learning curve for me :)

Many thanks
We've just done this one. The chromatography solvent is the 1:9 propanone to petroleum ether one.
 
CLEAPSS also has another solvent: http://science.cleapss.org.uk/Resource/PP056-Thin-layer-chromatography-of-plant-pigments.pdf

Anyone tested them side by side, or is this solvent (the one CLEAPSS uses) suitable for the TLC plates?
We've not tried the CLEAPSS solvent but their instructions say to use TLC plates so it should be suitable.

The AQA notes say to use the 1:9 propanone to petroleum ether one (page 119).

https://filestore.aqa.org.uk/resources/biology/AQA-7401-7402-PHBK.PDF

Hope this helps.
 
Both SAPS and CLEAPSS list suitable eluting solvent blends, I carried out a side by side comparison a while ago both gave good separation with the CLEAPSS being marginally better.
 

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I am dong required practical 7, and I am trying to figure out what is in the chromatography solvent.

I have two solvents:

1:9 propanone to petroleum ether and

4:1:1 Butan-1-ol: Glacial acetic acid: Distilled water

If I recall there is also chromatography for amino acids, but I have only done A level OCR so it is a learning curve for me :)

Many thanks
Hi,
We are also running this now.
The pet ether, propanone mix isnt doing much for us, on paper as AQA suggests or on TLC plates. We have found the CLEAPSS one to be better so far.
On TLC plates, not paper.
 
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