Questions tagged [colloids]
A colloid is a substance in which microscopically dispersed insoluble particles are suspended throughout another substance.
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What allows for colloidal solutions of polymers to act like solutions despite the large size of polymers?
I have been introduced to a paragraph in my textbook that I am trying to understand.
Macromolecular colloids: Macromolecules in suitable
solvents form solutions in which the size of the ...
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Why are colloidal sol particles of acidic dyes negatively charged and basic dyes positively charged, when it should be the other way round?
From NCERT Class 12 Chemistry; Sri Aurobindo Marg, New Delhi, India; January 2019; p. 136:
Colloidal solutions of basic dyes like methylene blue are positively charged whereas colloidal solutions of ...
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Why is there preferential adsorption of a common ion during preparation of colloids by peptization?
There was a similar question asked here on Chem SE, but the answer was not very satisfactory to me, so I am asking a fresh question.
Peptization is the process of creating a colloid from a precipitate ...
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Brownian motion of asymmetric particles
The classic Stokes-Einstein relation ($D=k_BT/(6\pi\eta r)$) it is assumed that the particle undergoing Brownian motion is spherical, and experiences ordinary Stokes flow between (or during) ...
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How practically to determine dispersion's Hamaker constant using CCC?
I know that Hamaker constants can be determined from CCC data.
$$ccc=\frac{9.85 \cdot 10^4 \epsilon^3 k_B^5 T^5 \gamma^4}{N_A e^6 A^2 Z^6}$$
Where, $\epsilon$ is solvent dielectric constant, $N_A$ is ...
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Do lyophilic sols have an electrical double layer?
"There are two factors which are responsible for the stability of lyophilic sols. These factors are the charge and solvation of the colloidal particles".
Quoted from NCERT book of OC
But we ...
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Particle tracking in colloids and uniformity in fractional part function
I don't know if its right place to ask this question since chemistry and programming both are involved.
I was working on particle tracking of series of pictures (.tiff) of colloids. And I was Using ...
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How do lyophilic colloids reduce surface tension?
It's given in my textbook that the surface tension of lyophilic/hydrophilic solutions is lower than water.
But my intuition says, since in lyophilic solutions the interaction between a lyophilic ...
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When is it realistic to model diffusion without advection?
Brownian motion abounds in nature, but so does drift current. In theoretical models of solutions and colloidal suspensions it is sometimes assumed that advection is negligible. I'm wondering if this ...
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Why are nanoliposome encapsulated antibiotics still so unavailable despite being so effective?
I wasnt sure how the phrase the headline question really nor if this is the right place to ask it, but i'm primarily interested in the chemical synthesis aspect and the experience of chemists ...
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Are the particles of a colloid "solid"?
I want to understand what are the particles of a colloid in the microscopic scale. According to Wikipedia:
A colloid is a phase separated mixture in which one substance of
microscopically dispersed ...
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How to prevent sedimentation of an EDTA suspension?
I tried to create a suspension of EDTA powder in glycerin with 1:1 ratio. I keep facing problem of EDTA sedimentation. I've tried other ratios also but this was the only one which formed least amount ...
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What is the influence of citrate on PEG-modified polyacrylamide hydrogels?
I've been having a puzzle explaining the experimental results with the citrate anions and PEG modified polyacrylamide:
According to the experimental data there is a hydrogel swelling whenever citrate ...
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Actual color of colloids [closed]
I have read that the color of colloid depends upon the wavelength of light scattered by the dispersed phase and also in the sense in which the receiver receives the light.
If all of this depends on ...
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Boilling colloidal silver?
I have some colloidal silver that i bought from a shop. It is 18ppm, however, I need a higher PPM and I can't seem to buy it anywhere where I live.
If I boil this colloidal silver, would it make the ...
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