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Cambridge Chemistry Challenge

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Reply 2360
Ok for the Rg it really long winded, are you familiar with binomial expansions (p+q) etc and ncr. You must form probability equations for r=1 (1 nitrogen 15) and r=2 (2N15) where n is the total glycine molecules. When the probability for r=2 is larger than for r=1, you know its more likely to have 2 N15 than 1N15. Thats all ill say though, kinda took ages trial and error etc.
any hints for silver?
Original post by bigBOI111
Rg question is about the hypergeometric distribution


Can't tell if you're being truthful or not, but if that is the case, then FML.
Hypergeometric distribution helps, but you need to understand permutation groups
Original post by bigBOI111
Rg question is about the hypergeometric distribution

Thats what i used for rg.
took ages tho :/
Original post by fizzers
https://support.google.com/maps/answer/18539?hl=en

This should help a little. Format it into a decimal then search it in google maps


Thank you! I was doing it on the google maps app on my phone so it didn't show me that...how do we get an Mr from this though?
I'm not going to give you the answer
Hmm... I imagine all these new members that have just joined and are solely posting on this are possibly not the most reliable of people.
Reply 2368
Silver: Its to do with a scale (red to Blue) and how a specific molecule changes in this property with a certain condition changing (the values on the left). Not gonna give it away completely though, sorry.
Original post by CJG21
Hmm... I imagine all these new members that have just joined and are solely posting on this are possibly not the most reliable of people.

Nah mate we got good rep.
anyway i used these links extensively with rg...http://en.wikipedia.org/wiki/Hypergeometric_distribution
http://mathworld.wolfram.com/HypergeometricDistribution.html
For copper I got a place called droux is this not correct?
Reply 2371
Original post by williamtong
come on, just give me an equation where i can actually put number into and work it out myself..... i dont even understand the question, i dont want the final answer, just tell me how to work it out


For Rg? I really cant you have to make your own equations and understand it to work it out, you need to keep changing the variables also, sorry its not just plugging in numbers
it just like to say that wijay43 is actually trying to help you guys, so do listen to him
:smile:
Reply 2373
Original post by williamtong
ok... so what type of equations do i have to use? and where r the variables from?
please teach me so i can actually learn something new


Its binomial expansions, like nCr and (p+q). Its C2 maths. Cant really teach you tbh, the final answer range is quite large though. Im gunna have to go now however, sorry.
How do you get from the date to the Mr on Cu? :confused:
The answer to Rg is <2000 if that helps at all
Original post by bigBOI111
The answer to Rg is <2000 if that helps at all

but >500
Reply 2377
Original post by bigBOI111
The answer to Rg is <2000 if that helps at all


Ok ignore this its wrong.
Original post by rabirabbit
How do you get from the date to the Mr on Cu? :confused:


Just google skylabs molecular mass
Original post by WiJay43
Silver: Its to do with a scale (red to Blue) and how a specific molecule changes in this property with a certain condition changing (the values on the left). Not gonna give it away completely though, sorry.



thanks but im still completely lost...

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