Questions tagged [absorption]
In chemistry, absorption is a physical or chemical phenomenon or a process in which atoms, molecules or ions enter some bulk phase – gas, liquid or solid material.
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Why do some molecules show non-symmetric absorption and emission bands?
I'm looking at a molecule of [Ru(bpy)3]2+ in water and the absorption and emission bands are not symmetrical. I want to know why the mirror image rule doesn't apply here. Is this because of the MLCT, ...
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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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Lipinski's Rule of 5 Oxygen Rules
I would like clarification on the role of oxygen as a hydrogen bond acceptor in Lipinski's Rule of 5 (for drug absorption). I have learned in my medicinal chemistry class that both electron pairs from ...
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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 ...
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Are there chemicals that absorb and release upon heating oxygen more efficiently than potassium oxide? [closed]
$\ce{K2O}$ absorbs oxygen forming $\ce{K2O2},$ which decomposes to $\ce{K2O}$ and $\ce{O2}$ at 500 °C. This means that $\ce{K2O}$ can absorb up to 17% its mass of oxygen. Are there other substances ...
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Is there a visible change to baking soda when it reacts with odour?
For example, would a box of baking soda in a fridge lose weight as it absorbs odor? How long would it take to drop 100 g?
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Spices are absorbed or adsorbed in food?
When we cook food, we add several spices and condiments which enhance color, taste and smell. Are these spices and condiments just adsorbed on the food particles? Or are they absorbed? For example ...
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Plasticisers and other impurities from polyethylene laboratory bottles?
Does polyethylene (PE), widely used for wash/squirt bottles in labs, contain soluble compounds such as plasticizers that can accumulate in organic solvents (e.g. alcohols, acetone) after prolonged ...
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Will charcoal briquettes (not activated) absorb water out of the air in the house in a subtropical climate?
I live in Florida, an incredibly wet environment where it's very difficult to get moisture out of house without using a dehumidifier 24/7, which is too expensive. Would charcoal briquettes be of any ...
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Calculation of silver nanoparticle size using Mie Theory
I have synthesized silver nano-particles and I wish to determine the approximate particle size using the wavelength that was most absorbed according to its absorption spectrum.
I find out that Mie ...
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Resonance condition for absorption of energy
In NMR, for example, why it is not possible to excite nuclei from one spin state to another using energy of arbitrary frequency?
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Sensitivity of CoSi2 to hydrogen
It is known that palladium is quite sensitive to hydrogen, i.e., has an extraordinary ability to absorb hydrogen. I was reading a paper that talks about the fabrication of a Pd based sensor for ...
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Difference in the absorption spectrum of gaseous atoms and complex ions
An absorbance spectrum is a graph that shows how much light is absorbed by the material at each wavelength of light. Both spectra are due to electronic transition, but for gaseous atoms, this spectrum ...
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Negative absorption coefficient
What does a negative absorption coefficient mean?
In detail - I participated in a Synchrotron virtual laboratory. I have to analyze the results and understand what a negative absorption coefficient ...
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Auxochrome groups and red shift
Wikipedia states that "An auxochrome is known as a compound that produces a batochromic shift, also known as a red shift because it increases the absorption wavelength, thus approaching infrared ...
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