Aqa set their A*'s at 90% UMS, and after that the grade boundaries for an A are the total pupils scored below A* and find the 10% then again for BCand D, yet I will make a petition, where should I put it? Change.org? Or Facebook?
Aqa set their A*'s at 90% UMS, and after that the grade boundaries for an A are the total pupils scored below A* and find the 10% then again for BCand D, yet I will make a petition, where should I put it? Change.org? Or Facebook?
I put the same as you - it was either that or r=k[H+], but i put that I2 was not in the rate equation before because it was in excess (guessing), so as it is not in excess I put it in
This was a dodgy question, I guess it as r=k[I2][H+], what did you put down?
I agree the question was dodgy because it didn't state I2 wasn't in RDS, it just asked you to suggest why. It could have been that I2 was in massive excess in which case it would appear to be pseudo order. This was a very tricky question I thin.... I think it's safe to say propanone was pseudo order, so would appear to be zero order, but they may still include in rate equation? In which case it'd just be the same? However I think this would be very strange of AQA... I went with r=k[h+] in the end using the logic I2 not in rds and the ketone is in massive excess so won't affect the rate... Hopefully this is right!
Using AgNO3 is the answer AQA were probably looking for however i wrote the same as you and im 99% we are right
Is this for the acyl chloride and the ketone? I put silver nitrate too, but now I realise that there was a chlorine on both of them so silver nitrate would produce a white ppt with both :/
I agree the question was dodgy because it didn't state I2 wasn't in RDS, it just asked you to suggest why. It could have been that I2 was in massive excess in which case it would appear to be pseudo order. This was a very tricky question I thin.... I think it's safe to say propanone was pseudo order, so would appear to be zero order, but they may still include in rate equation? In which case it'd just be the same? However I think this would be very strange of AQA... I went with r=k[h+] in the end using the logic I2 not in rds and the ketone is in massive excess so won't affect the rate... Hopefully this is right!
It may be possible that they allow more than one answer (but not one with iodine) I would have thought. If lots of candidates offer alternatives (which is possible) and as long as you justify it properly, this may be the case.
Or M1 may be dependent on a properly explained M2.
It may be possible that they allow more than one answer (but not one with iodine) I would have thought. If lots of candidates offer alternatives (which is possible) and as long as you justify it properly, this may be the case.
Or M1 may be dependent on a properly explained M2.
I agree, seems logical they will award M1 based on reasoning of M2
For the Cl containing ketone and acyl chloride test, although both have a Cl so you would think both would form a white ppt with silver nitrate... is the haloalkane reactive enough to release the Cl? Do you not have to release the halide first with aqueous NaOH for that to happen?
... just me trying to defend my pitiful case for 3 more marks
I agree, seems logical they will award M1 based on reasoning of M2
Mind you, I think I had a VERY lucky guess of the last compound on the 9 mark analysis, as I wrote down as much info as I could and sort of half-guessed it with 30 seconds left.