The Student Room Group

Cambridge Chemistry Challenge

Scroll to see replies

Original post by Silverland
Rg is awful. You can spend hours on it and still struggle. Just a warning~!

(though Gold isn't that bad for an A2 chemist at all)


I agree, ive just spent over an hour on the Rg question and still havent got it :/
Original post by Silverland
in that searching the elements given all together will bring up links containing them and 3 others

it's just a dumb word game really though. Zilch chem


Got it. Worst question I've ever seen on this website.
Reply 1022
how do we get the concentration of vinegar ions in gold
White wine vinegar is about 4-5% acetic acid, but I'm not sure if that helps.
Got Gold, make sure you give your answer to about 5 dp. Write out the Ka expression, that should help.
Reply 1025
help on gold been stuck on it for years
Okay, Rg is hard. Could possibly use area density of graphene and circumference of a cylinder if I knew the diameter of the tube.
Original post by Snakefingers13
Okay, Rg is hard. Could possibly use area density of graphene and circumference of a cylinder if I knew the diameter of the tube.


Yeah, I've been having the same problem, how can we find out what diameter it is?
Reply 1028
Can someone PM me gold? I'm soooo stuck
Can someone also PM me gold?
stuck is an understatement :c
Me too, I've been stuck on it for a while...
Reply 1031
pm gold pleasssssssse
Reply 1032
still stuck on entry level
help, hint, anyone
Look: Ka = [H+][X-]/[HX]

You know pKa and pH. It's rather straightforward then.
Reply 1034
how do we know pka
Original post by nihar97
how do we know pka
That's the easy bit. Come on...
OMG, gold and its decimal places is annoying.
Original post by Ferrarifan 27
Yeah, I've been having the same problem, how can we find out what diameter it is?

I keep reading figures of around 1 nm to 1.2 nm, but plugging those in gives me stupid answers.
Original post by Snakefingers13
I keep reading figures of around 1 nm to 1.2 nm, but plugging those in gives me stupid answers.


Wiki says "Nanotubes have been constructed with length-to-diameter ratio of up to 132,000,000:1" but that doesn't give the answer either..?
There must be some simpler method for Rg

Quick Reply

Latest