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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Is the water absorbed by sodium polyacrylate available to react?
I'm curious whether the water absorbed by sodium polyacrylate would react with alkali metals, or be trapped by the sodium polyacrylate.
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tolerable error, CASSCF simulation of UV/Vis spectrum
Please forgive my ignorance of experimental spectroscopy. I am a computational chemist, not an experimental one. My question is: what would be considered a tolerable or reasonable difference between ...
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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 ...
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Vibronic coupling: How do I determine the new point group after vibration?
So I was recently discussing the transitions in Egyptian Blue ($\ce{CaCu[Si4O10]}$) with some of my students, who had to prepare this compound. What I like in particular in this case is how, at least ...
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What substance consumes oxygen from atmospheric air [closed]
I'd like to find an economical substance that will consume oxygen from a container. Steel wool comes to mind but I don't have an intuition how feasible it would be.
The chamber is 5 gallons in size ...
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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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Hygroscopic Substances and Drying Agents
My book says:
Most of the hygroscopic substances are drying agents
Based on what I read on several websites, I think dehydrating agents also act as drying agents. If so, all dehydrating agents ...
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What kind of drugs can be absorbed through skin? [closed]
Some drugs such as nicotine can be administered through skin. I thought the layers of skin are designed to prevent in-flow of any chemical/germs. Not all drugs get absorbed in this fashion. So do ...
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What is the relationship between emission and fluorescence?
A molecule exposed to a photon with some energy is put into an excited state, and emits a photon of some energy when it returns to ground state.
The photon that provided the energy for excitation ...
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What is the difference between dissolution and absorption?
Let us first look at the definitions from Gold Book:
Absorption:
The process of one material (absorbate) being retained by another (absorbent); this may be the physical solution of a gas, liquid, ...
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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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Explaining color differences using bond conjugation
I'd like to ask about how the color differences between the dyes methyl violet and malachite green can be explained. Looking at the conjugated bonds of each, methyl violet seems to be more conjugated ...
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Finding the wavelength of maximum absorption of Tartrazine using Fieser-Kuhn
How would you use Fieser-Kuhn rules to calculate the wavelength of maximum absorption for tartrazine?
Fieser-Kuhn rules states that:
$\lambda_{max}=114+5M+n(48-1.7n)-16.5\ R_{endo} - 10\ R_{exo}$
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Determining the calcium content in cashews via titration?
I have been planning on an experiment for quite some time now (as part of my after-school chemistry club), but I still feel like I am missing something.
Due to my family's calcium deficiency, I ...
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Why does my absorbance change over time?
I have a solution of black phosphorus quantum dots suspended in water that I prepared by sonicating black phosphorus powder in n-methyl-2-pyrrolidone and centrifuging to isolate the quantum dots. ...
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