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Edexcel CHEMISTRY DOUBTS!!!!

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Blizz_rb93:
I have this question that is from Unit 1 Section A..

- Buckminsterfullerene is a carbon molecule with formula C60 which can trap metal ions its structure. Which of the following compounds of buckminsterfullerene would give a line of mass/charge ratio at 837.3 in a mass spectrometer??
A) Na4C60
B) K3C60
C) Ca3C60
D) AgC60

The markscheme says it's B but i dont get how they got it? and how do u find out the mass/charge ratio at 837.3 in the mass spectrometer?

Uchia:
answer is b just find the mr

the mr for k is 39.1

so (39.1*3) +(60*12) = 837.3

Blizz_rb93:

--- Quote from: damlaj on May 15, 2010, 07:44:29 am ---answer is b just find the mr

the mr for k is 39.1

so (39.1*3) +(60*12) = 837.3

--- End quote ---
oh lol ok thats easy XD

Summer :]:

--- Quote from: kim on May 14, 2010, 04:39:49 pm ---well as u go down the group the cationic size increases
so there is less polarisation (as the cation is big whereas for polarisation the cation should be small and the anion big)
less weakening of the CO or NO bond
thus the thernal stability increases

--- End quote ---


as you go down the group
the cationic size increases ( they are less polarising because the are more inner shell electrons repelling the outermost electrons therefore the positive nucleus has less control over its outermost electrons so its less likely to polarise the electrons of the anion towards)
they become less polarising...they are less likely to polarise the anion to break it apart and produce different compounds so they are more stable..less likely to break
so you need more heat to compensate for this weak polarising effect in order to break the compound apart to form other compounds..

Summer :]:
Does anybody know why the O-H group on the infrared spectrum is so broad? it says because of the hydrogen bonding..how is that??  ???

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