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Cambridge Chemistry Challenge

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Reply 1080
Original post by david2457
Can anyone pm the answer to rg please


Same here, thanks :smile:
Reply 1081
whats the relation between diameter and density?
K guys, they want a 2,2 nanotube. So just don't think too hard ahahahaha
For rg, I have the diameter. Do I use:1/1315*50500*diameter*pi? I tried that and it doesn't work
Rg is solved by finding the thinnest possible carbon nanotube, and it turns out you can do it the way I thought of involving surface area and area density of granite.

Not impressed with the questions this month. Copper and Silver were poor, Gold gave you no hint to increase your significant figures if you had an answer nearby and Rg was unnecessarily confusing.
And after thinking harder about the link for the picture in Silver, I think it might be Macromolecules in a sort of twisted chemistry pun.
Original post by Snakefingers13


Can you help me with my thinking?

Someone said the diameter is 2.2nm
times by pi to get circumference
and then times that by the length 50.5m
then times by the area density.

Is this right?
Original post by TheRocker
Can you help me with my thinking?

Someone said the diameter is 2.2nm
times by pi to get circumference
and then times that by the length 50.5m
then times by the area density.

Is this right?


The diameter is not 2.2 nm, rather I think that means a (2,2) nanotube in terms of indices. Research that.
At the minute I am working out the volume of the nanotube by doing Lr^2pi, (50500x(0.2x10-9)^2x3.14159...) and then dividing this value by the mass density of graphene, which I have found to be 1315 g per m^2. Am I on the right lines and getting one of my values wrongs or am I not on the right track?
The area density of graphene can be found on the Nobel Prize paper related to it.
I am using a diameter of 0.4nm, am I right in doing so?
Reply 1092
any hints on cupper and silver
Reply 1093
Work out Copper any hint on silver
Reply 1094
you are saying different things? I cant solve it with a lot of data!
Oh jeez, this Rg is driving me insane!
I think I've found all the values but I get something in the *10^-8 region, which I assume is far too small.
Also, where are the values of "50.5" and "50500" coming from for length? Shortest distance between england and france that I get is 34km?
Reply 1096
Can someone help me out with Gold? I completed the first three questions within ten minutes now this has stumped me.
Reply 1097
any hints to Rg
Finished! Remarkably few people have for this late in the day... Awkward questions or the NYE effect?

Original post by Lutski
Can someone help me out with Gold? I completed the first three questions within ten minutes now this has stumped me.




If gold is the one with pH, look up some equations for pH and pKa, you should notice something :smile:
Reply 1099
help me on Ag

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