In the proton NMR of 2-methyl-2- butanol http://sdbs.db.aist.go.jp/sdbs/cgi-bin/direct_frame_top.cgi why don't the hydrogens labeled 'C' receive separate splitting patterns if they are located on separate carbons.

The two 'C' methyl groups are in identical environments. They experience the same degree of shielding on average (it varies a bit as the single bonds rotate and the molecule samples conformational space, but these average out in the NMR pulse timeframe). They are also equivalent in their covalent bonds (they are both bound to the same carbon). Hence, all six hydrogens have identical chemical shifts and identical coupling (splitting pattern).

Is there anywhere I can find out what absorption lines correspond to what elements? Thanks

https://physics.nist.gov/PhysRefData/ASD/lines_form.html

3:22 what is a spectrograph please explain more clearly

A spectrograph displays more clearly the wavelengths of the visible spectrum. For example, it will show that red will have a longer wavelength but a shorter frequency than that of violet.

is there a gas, when electrically charged which creates a black color?

Nothing can emit a "black light" since black is considered the absence of light.

Why does neon light up when a current passes through it? Is it because of a reaction?

yes, it is a reaction. the neon gas absorbs the electric current passing through it, therefore emitting light photons

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Kristine BouChamoun
Posted 10 years ago. Direct link to Kristine BouChamoun's post “In the proton NMR of 2-me...”
In the proton NMR of 2-methyl-2- butanol http://sdbs.db.aist.go.jp/sdbs/cgi-bin/direct_frame_top.cgi why don't the hydrogens labeled 'C' receive separate splitting patterns if they are located on separate carbons.
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- RBPaulsen
  Posted 9 years ago. Direct link to RBPaulsen's post “The two 'C' methyl groups...”
  The two 'C' methyl groups are in identical environments. They experience the same degree of shielding on average (it varies a bit as the single bonds rotate and the molecule samples conformational space, but these average out in the NMR pulse timeframe). They are also equivalent in their covalent bonds (they are both bound to the same carbon). Hence, all six hydrogens have identical chemical shifts and identical coupling (splitting pattern).
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  (3 votes)
Ranusha Nanayakkara
Posted 5 years ago. Direct link to Ranusha Nanayakkara's post “Is there anywhere I can f...”
Is there anywhere I can find out what absorption lines correspond to what elements? Thanks
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(4 votes)
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- Davin V Jones
  Posted 5 years ago. Direct link to Davin V Jones's post “https://physics.nist.gov/...”
  https://physics.nist.gov/PhysRefData/ASD/lines_form.html
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Noah
Posted 9 years ago. Direct link to Noah's post “What does spectroscopy me...”
What does spectroscopy means?
And where does it come from?
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- Louis Escuela
  Posted 7 years ago. Direct link to Louis Escuela's post “From the latin Spectre or...”
  From the latin Spectre or ghost and from the greek scope or watcher. Some people thought they looked like ghosts.
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Titan427
Posted 7 years ago. Direct link to Titan427's post “what is the color of nitr...”
what is the color of nitrogen gas when electrically charged in a neon tube?
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Yadilit
Posted 8 years ago. Direct link to Yadilit's post “3:22 what is a spectrogra...”
3:22
what is a spectrograph please explain more clearly
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(2 votes)
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- baysim
  Posted 8 years ago. Direct link to baysim's post “A spectrograph displays m...”
  A spectrograph displays more clearly the wavelengths of the visible spectrum. For example, it will show that red will have a longer wavelength but a shorter frequency than that of violet.
  Button navigates to signup page
  (2 votes)
Titan427
Posted 7 years ago. Direct link to Titan427's post “is there a gas, when elec...”
is there a gas, when electrically charged which creates a black color?
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(2 votes)
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- AegonTargaryen
  Posted 7 years ago. Direct link to AegonTargaryen's post “Nothing can emit a "black...”
  Nothing can emit a "black light" since black is considered the absence of light.
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  (2 votes)
Marta Rabello
Posted 9 years ago. Direct link to Marta Rabello's post “What about the double vis...”
What about the double visible spectrum that appears at
2:48
?? I believe it´s not right!
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gabriella
Posted 9 years ago. Direct link to gabriella's post “What is atomic emission a...”
What is atomic emission and absorption in relation to spectroscopy?
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Thomas Manik
Posted 8 years ago. Direct link to Thomas Manik's post “How do they get those ele...”
How do they get those elements into the tubes?
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Kenny
Posted 8 years ago. Direct link to Kenny's post “Why does neon light up wh...”
Why does neon light up when a current passes through it? Is it because of a reaction?
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(1 vote)
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- Titan427
  Posted 7 years ago. Direct link to Titan427's post “yes, it is a reaction. th...”
  yes, it is a reaction. the neon gas absorbs the electric current passing through it, therefore emitting light photons
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  (2 votes)

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