All Questions
Tagged with absorption spectrophotometry
5
questions
5
votes
1
answer
493
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The reason for selection of wavelengths in the spectrophotometry of Quinoline Yellow SS
The absorption spectrum for Quinoline Yellow SS has peaks at 224 nm and 414 nm, and a trough at 337 nm.
This experiment (see page 31), selects 224, 337 and 414 nm to be used in the spectrophotometric ...
4
votes
1
answer
2k
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How to determine chlorophyll content from spectrophotometry data (absorbance vs wavelength)?
I boiled spinach solution (spinach leaves and 90% methanol) in solutions of varying $\mathrm{p}H$. I used a spectrophotometer to obtain wavelength ($\lambda$) vs absorption, and want to investigate ...
- 71
2
votes
1
answer
3k
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The negative absorbance values in the baseline measurement
In the spectrophotometric analysis(uv-vis-NIR) of ITO Nanoparticles in tetrachloroethane using a double beam instrument baseline was measured with 2 identical cuvette with solvent only. This gives me ...
- 61
3
votes
2
answers
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When making a calibration curve, do we have to use the wavelength at maximum absorbance?
If you are making a calibration curve for $\ce{CuSO4}$ where you plot absorbance against concentration, does the wavelength have to be exactly at the maximum of the peak? Or can it be somewhere else ...
- 73
2
votes
1
answer
159
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Effective attenuation coefficient for polychromatic light
The Beer-Lambert law gives the optical intensity of collimated light as a function of depth $z$ as:
$$I(z)=I_{0}\mathrm e^{-\gamma z},$$
where $\gamma = \alpha + \beta$ is the wavelength-dependent ...
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