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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Using table salt as a way to limit humidity in an unoccupied house
We own a static caravan in the UK (Snowdonia region, so rainy and wet all year round, moderately cold winters) and we leave it unoccupied during Winter (Oct-Feb).
We were advised of an apparently ...
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What is the reason for the blue color of an ammoniated electron?
I am quoting a line from a book regarding reactivity of alkali metals with liquid ammonia.
The blue colour of the solution is due to the ammoniated electron which absorbs energy in the visible region ...
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Relative strength of desiccants
Is it meaningful to characterize the relative strength of desiccants? For example, is there a measure of hygroscopy, or an ordering of desiccants, such that higher ones will always dry lower ones?
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What is the cause of hygroscopy?
Hygroscopy is the ability of a substance to attract and hold water molecules from the surrounding environment.
Why are some compounds hygroscopic and others are not? What is it about their ...
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If polyethylene glycol (PEG) is hygroscopic, how does it protect wood?
Archaeologists and conservators use polyethylene glycol (PEG) to replace water inside wood to protect it from shrinking and expanding with changes in humidity. But it is hygroscopic—even more so than ...
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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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New finding in cobalt compound that absorbs oxygen - is it really a breakthrough?
Very recently Chemical Sciences published results of the discovery of a new cobalt compound that can absorb oxygen at presumably a higher capacity than what has been achievable before. The paper is ...
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When pigments absorb light only around a single particular wavelength, why aren't they still white?
I'm trying to understand how organic molecules get their colour.
One major factor are conjugated double bonds which create delocalized pi-orbitals (e.g. https://en.wikipedia.org/wiki/...
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What chemicals could absorb/adsorb ambient atmospheric methane?
From an article in the New Scientist in 2010,
Since pre-industrial times, methane levels in the atmosphere have risen from around 715 parts per billion to nearly 1800 ppb, claims Folberth. "If ...
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Can physical absorption happen despite the formation of products?
As far as I know, the absorption of $\text{SO}_2$ in water goes under physical absorption, meaning the sulfur dioxide bubbles are held in place by Van der Waals forces, in this case Keesom forces, ...
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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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Improving efficiency of absorption refrigerator (ammonia+hydrogen)
Apologies if this is not the right forum for this question, I checked the Physics side and there's no questions on this, whereas there's at least one other question here about absorption refrigeration....
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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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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 ...
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Why is grease from cooking hard to remove from wood?
Cooking oil that jumps from a frying pan in use and over time accumulates around the frying pan on a wooden surface is sticky and hard to remove.
My question is why. Why is it hard to remove? What is ...
