Questions tagged [adsorption]
The adhesion of atoms, ions, or molecules from a gas, liquid, or dissolved solid to a surface.
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Why are van der Waals' forces between gas molecules strong near its critical temperature?
My textbook says
…easily liquefiable gases i.e. with higher critical temperatures are readily adsorbed as van der Waals' forces are stronger near the critical temperatures.
What I do understand is ...
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What is negative adsorption? [closed]
In adsorption, the concentration of adsorbate is greater on the surface. So, how is it possible that the solvent will be more on the surface and the solute (adsorbate) in the bulk… or does solute not ...
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How to obtain the linear form of Redlich Peterson isotherm model by algebraic transformation or any other ways? [closed]
The Redlich Peterson isotherm model is known as:
$$
\begin{aligned}
q_e=\frac{AC_e}{1+BC^g_e}
\end{aligned}
$$
Is there any way to obtain the linear form of this equation by algebraic transformation ...
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hydrodynamic thickness of polymer vs. concentration of electrolyte?
I've measured the hydrodynamic thickness of a NaPSS layer on polystyrene latex and plotted it against the concentration of the supporting electrolyte, NaCl.
My graph shows a general decrease in ...
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Why Freundlich adsorption isotherms fails at high pressure conditions?
Experimentally it was determined that extent of gas adsorption varies directly with pressure, and then it directly varies with pressure raised to the power 1/n until saturation pressure Ps is reached. ...
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Is activated charcoal an air purifier?
It's well known that activated charcoal is an adsorbent and due to very big surface area per unit of mass it can adsorb a lot of particles.
Let's take as an example for my question this product on ...
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Order of reaction in adsorption process
(1) $\ce{PH3(g) <=>[W]PH3(adsorption)->[W]P(s) + 3/2 H2(g)}$
The decomposition of phosphine on tungsten surface at low pressure is a pseudo first order reaction. This is because the rate of ...
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Dangers of using activated carbon past its lifespan
Activated carbon (AC) is one of the most widely used media for water filtration. It's effective at removing chlorine taste and odor, and it's recognized as being safe.
However, most activated carbon ...
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Why does Freundlich adsorption isotherm not have a term for surface area?
Why does Freundlich adsorption isotherm not have a term for surface area?
The formula given by Freundlich adsorption isotherm:
$$ \frac{x}{m}= k P ^{1/n}$$
Where $x$ is the mass of gas adsorbed ...
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What are molecular species?
I am in high school learning about adsorption for the first time. My school textbook says:
"The accumulation of molecular species at the surface rather than in the bulk of a solid or liquid is ...
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Preparation of Copper (II) Sulfate Pentahydrate Solution
how would you make a solution of Copper (II) Sulfate Pentahydrate to achieve 150, 200, 250 and 300 mgL−1 concentration of copper? I do not have the anhydrous version of the solute. Also, when I ...
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Why enthalpy of adsorption is negative?
I have already read Is adsorption exothermic, and if so, why? but it didn't answered my query.
To illustrate, let's take a hypothetical vacuum space. In that space, there is a solid and a gas, the ...
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Is the adsorption of dissolved iodine onto activated carbon physical adsorption or chemical adsorption?
For an experiment, I am looking to see the effect of temperatures from 0–100 °C on the efficacy of activated carbon as an adsorbent. My adsorbate is iodine and I am confused as to whether the ...
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How did Zyklon hold and release HCN?
$\ce{HCN}$ is notoriously unstable: It boils at room temperature, and it tends to polymerize when concentrated in unbuffered liquid form. Yet $\ce{HCN}$ was for decades widely used as a fumigant ...
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How to quantify the adsorption affinity of gases?
Is there a term/quantity which shows how 'sticky/adsorptive' a molecule is? I am interested in gas adsorption on steel surfaces in our mass spectrometer and would like to estimate which gases have a ...
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