yeah i can't figure out the last one! its not DNA. so what is it??? anymore clues on the 'weird hydrocarbon'?![]()
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Cambridge Chemistry Challenge watch
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- 01-02-2012 18:58
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- 01-02-2012 19:31
The difference between the Carbon and the Hydrogen is 1.
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- 01-02-2012 19:38
Any other clues?
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- 01-02-2012 19:41
anyone know the silver answer :/
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- 01-02-2012 20:16
(Original post by Degreen)
Something to do with Polycyclic Aromatic Hydrocarbons? -
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- 01-02-2012 20:26
(Original post by savage903)
anyone know the silver answer :/ -
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- 01-02-2012 21:13
i think im going along the right lines for the last one
i dont know how to do a spioler so i will do my next paraghrapgh in white, will somebody able to tell me if im right?
you find the density of soduim. find volume of the sphere. but i dont know why it gives you the other value for distance.... and then you just do some maths with it to get moles? -
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- 01-02-2012 21:47
(Original post by chill543)
i think im going along the right lines for the last one
i dont know how to do a spioler so i will do my next paraghrapgh in white, will somebody able to tell me if im right?
you find the density of soduim. find volume of the sphere. but i dont know why it gives you the other value for distance.... and then you just do some maths with it to get moles?
without the spaces
Also, yes, you do do what you wrote and the answer starts with a 5, to keep you on track. -
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- 01-02-2012 21:51
(Original post by loopy786)
You do [ SPOILER ] sidiudbusabicbas [ / SPOILER ]
without the spaces
Also, yes, you do do what you wrote and the answer starts with a 5, to keep you on track.
Spoiler:Showbut it was to like 5 places (e.g 10000 = 5 places) + thanks for the tip on spoilers! -
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- 01-02-2012 21:55
(Original post by chill543)
i must have been clos my answer started with 6!
Spoiler:Showbut it was to like 5 places (e.g 10000 = 5 places) + thanks for the tip on spoilers!
Spoiler:ShowYou might find the number 24.804 useful... just saying. -
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- 01-02-2012 22:49
(Original post by chill543)
i think im going along the right lines for the last one
i dont know how to do a spioler so i will do my next paraghrapgh in white, will somebody able to tell me if im right?
you find the density of soduim. find volume of the sphere. but i dont know why it gives you the other value for distance.... and then you just do some maths with it to get moles?Spoiler:ShowYour answer probably started with a 6 because you didn't know why it gives you the other value for distance. This would be because the liquid sodium is bounded by the outer sphere AND the inner sphere and so only occupies the region between. Therefore the volume of sodium is the volume of the larger sphere minus the volume of the smaller sphere.Last edited by CM23925; 01-02-2012 at 22:53. -
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- 02-02-2012 16:40
ok im back everyone and this is my working out so far. Dont cheat (even though its wrong!)
Spoiler:Show
Density of sodium = 0.97g/CM3 = 0.0422mol/cm3 = 0.0422x10^6mol/cm3
then vol of sphere.
1.333piR^3 = 13 (for first) and 0.5 for second.
diffrence is 12.5
then 12.5*4.22*10^4= mol = 527500...
seems a bit big, but any way its wrong :P
corrected then for density at melting piont but i still cant see what im doing wrong.. unless its in the math.... ill look out for that number though loopy :P
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- 02-02-2012 17:59
(Original post by loopy786)
What was silver; the name of the reaction? -
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- 02-02-2012 18:01
no sorry its the one where it says whos the first scientist to publish synthesis of this molecule
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- 02-02-2012 18:14
(Original post by savage903)
no sorry its the one where it says whos the first scientist to publish synthesis of this molecule
It's a drug to treat cancer, and is harvested from pacific yew. That's an hint. -
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- 02-02-2012 18:16
(Original post by chill543)
ok im back everyone and this is my working out so far. Dont cheat (even though its wrong!)
Spoiler:Show
Density of sodium = 0.97g/CM3 = 0.0422mol/cm3 = 0.0422x10^6mol/cm3
then vol of sphere.
1.333piR^3 = 13 (for first) and 0.5 for second.
diffrence is 12.5
then 12.5*4.22*10^4= mol = 527500...
seems a bit big, but any way its wrong :P
corrected then for density at melting piont but i still cant see what im doing wrong.. unless its in the math.... ill look out for that number though loopy :P
Spoiler:Show
So the difference exactly is 12.48, actually, without rounding.
Then you make that into cm-3 which is 12480000
12480000/ [22.8... aka molar mass/ 0.927 aka density at melting point]
Which is 12480000/24.804 or something
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- 02-02-2012 18:50
(Original post by loopy786)
Okay it's because of how you've done some of it.
Spoiler:Show
So the difference exactly is 12.48, actually, without rounding.
Then you make that into cm-3 which is 12480000
12480000/ [22.8... aka molar mass/ 0.927 aka density at melting point]
Which is 12480000/24.804 or something
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- 02-02-2012 19:11
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- 02-02-2012 20:38
Finished
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- 180
- 02-02-2012 23:27
Been looking into the last question for ages! Seriously can't find anything to help anywhere! Someone help!! On the other hand, I've found out lots about Arecibo which I don't really care about! Haha
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