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***2013 LC Chemistry Before/After***
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Why does each element have a unique emission spectrum, other than because they all have unique electronic configurations?
This is most definitely a question to test all of your knowledge, it is in no way me trying to exploit you all for your knowledge. Of course not.
Hmm so when elements become "excited" electrons move from lower energy levels to higher ones. They are very unstable here and fall back to their positions. They emit definite energy when they fall back and each element has a different amount of energy released
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MarieCurie22 wrote: »Unique number of shells, different samples (ie some contain more atoms...less energy absorbed by each)
Different sub levels (although that essentially the same as the electronic config....hmmm....each atoms absorb different frequencies of light?
All samples contain the same number of atoms (avogadro number) The only thing that changes to give the Balmer series is, the normal emitting a photon/packet of energy as it transitions from one state to another. Although the movement is basically the same, the energy for each transition is different depending on the attractive forces between the electron and the nucleus, hence the different lines in the series
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All samples contain the same number of atoms (avogadro number) The only thing that changes to give the Balmer series is, the normal emitting a photon/packet of energy as it transitions from one state to another. Although the movement is basically the same, the energy for each transition is different depending on the attractive forces between the electron and the nucleus, hence the different lines in the series
No all samples dont contain the same number of atoms....all moles contain the same number not samples!0 -
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Ok guys Ionisation energy is tipped for tomorrow so...heres my tricks of the trade :P
Mickeys hat and cloak represent the ATOMIC RADIUS...
-Decreasing across (Mickey's hat gets narrower):
-Increase in nuclear charge (ie more and more protons being added stronger pulling force from the nucleus, which in turn makes the radius smaller)
-Also no screening effect of inner electrons!
-Increasing Down (Like Mickey's cloak getting wider)
-Addition of new shells down the period
-Because of the addition of the new shells this means there is a screening effect of inner electrons!
Ionisation Energy:
The energy required to remove the most loosely bound electron from a neutral atom in its gaseous state.
Ionisation energies....
-Increase across the period:
-Due to the decrease in atomic radius (See above)
-Increase in atomic charge (more protons)
-Decrease down the period:
-Due to increasing atomic radius.
-Screening effect of inner electrons!0 -
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outnumbered wrote: »OH I hope this "all-nighter" pays dividends tomorrow!!!
En primer lugar, tengo El Espanol, y después, tengo la quemica!
Best of luck to all!!!
¡Buena suerte!0 -
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haha i didnt even do it came up 2 years in a row perior to 2012 dont see it again hopefullyHamza Malik wrote: »I'll kill myself is the benzoic acid experiment comes up. I don't know it well
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Deleted User wrote: »Quick clarification. Is it that either atmospheric or industrial chemistry will be the option?
Yes itll say answer either or i think 0 -
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MarieCurie22 wrote: »Yes itll say answer either or i think
I thought it was one of A or B comes up in each option, like say our year did atmospheric and industrial but other schools did materials and electrochemistry,
then the question that comes up will have, for example, the option of atmospheric or electrochemistry. Or have I that wrong?
Either way, I only know industrial. Premier Periclase is my bítch 0 -
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Acciaccatura wrote: »I thought it was one of A or B comes up in each option, like say our year did atmospheric and industrial but other schools did materials and electrochemistry,
then the question that comes up will have, for example, the option of atmospheric or electrochemistry. Or have I that wrong?
Either way, I only know industrial. Premier Periclase is my bítch
Tbh half the schools dont bother with it....stick to what you know without the option and if you feel capable go for it!0 -
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Prodigious wrote: »Gonna nail it.
Thats the spirit sick of people saying otherwise...
Whats the timming today?0 -
MarieCurie22 wrote: »Not neccasaily the thinest every time....the burette is more accurate is it measures ever drop, the graduated cylinder wouldnt "read" a tiny difference like a burrette...
How ever the volumetric flask is better than any other because of its thing neck....its not the thinnest apparatus!
Thank you Just in this particular question I was asked either a Burette or a graduated cylinder
And I'm pretty sure you're right about the option it'll only be atmosphere or industry. Hoping for atmosphere 0 -
MarieCurie22 wrote: »Thats the spirit sick of people saying otherwise...
Whats the timming today?
Timing? Never really pay attention to it, always seem to have a good 30 minutes at least at the end. I'll probably do Q4 5 and 6 first, then go back and to the experiments, and then have a look at what's left. What order are you doing?0 -
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Prodigious wrote: »Timing? Never really pay attention to it, always seem to have a good 30 minutes at least at the end. I'll probably do Q4 5 and 6 first, then go back and to the experiments, and then have a look at what's left. What order are you doing?
All experiments first do all if you can gives you so much space at the end
Then q 4, 7.8.9
Then the ones with the options 0
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