# Tag Info

Accepted

### Why not use all the colours in colorimetry?

Why not send in white light (with all the wavelengths at once)? This is certainly and routinely done today. The main thing is how much price are we willing to pay? In a rigorous sense, colorimetry ...
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### Visible Light Spectrophotometer Recommendations

Disclaimer: I'm not affiliated with any company However, Ocean Optics cuvette spectrophotometers are a good choice This model is used in some undergraduate labs and is good because the cuvette ...
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### Visible Light Spectrophotometer Recommendations

Good spectrometers in "new, unopened" condition are out of your budget. Their prices start at about 2000 USD. This also includes the spectrometers specifically made for education—like the ones from ...
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### Notation for excited states

As has already been mentioned in comments, those letters and numbers for each state correspond to their symmetry, specifically the symmetry of the (purely electronic) wavefunction. For more ...
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### Why not use all the colours in colorimetry?

The previous answers by @Buck Thorn and @M. Farooq are very good, but not quite complete. The main advantages of FT UV-Vis spectroscopy would be 1) accuracy of wavelength (or wavenumber) determination ...
• 4,470
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### Reason for usage of Metal chlorides and Platinum or Nichrome wires in flame test

Metal chlorides are usually much easier volatilized than oxides or sulfates. They melt or sublime at temperatures much lower than 800°C. So they are volatilized in any flame like Bunsen burners. ...
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• 27.8k

### What is an exocyclic double bond?

The double bond B is exocyclic to ring 2 as it is attached to an atom which is shared between ring 1 and ring 2 while the double bond A is not connected to any ring 2 atoms and is within just one ring,...

### Is a hue indistinguishable from its equivalent frequency of light?

Certainly not The problem is not, strictly, one of physics but one of perception. The eye doesn't detect individual wavelengths of light but the relative amount of red, green and blue light (but the ...
• 33.1k
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### UV Absorption of iodine with some solvent

Iodine is highly polarisable and will form a (Mulliken) charge-transfer complex with many aromatics. Very many pairs of donor - acceptor pairs do this and have been studied for approx $100$ years, see ...
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### Different force constant in ground vs excited state in spectroscopy

At the risk of providing a somewhat circular answer, in the harmonic approximation of an interatomic potential, the force constant is a measure of the force of attraction between the atoms (in a ...
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### Why do some molecules show non-symmetric absorption and emission bands?

From the Jablonski diagram, The mirror image is only true if you are talking about transitions from $S_0$ to $S_1$ (absorption) and $S_1$ to $S_0$. Also read about Kasha's rule. Quinine is the ...
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