All Questions
Tagged with surface-chemistry surfactants
19 questions
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What is the highest known temperature where micelles exist?
What are the two liquid phases involved in the formation of roughly spherical micelles at highest possible temperatures? What about a surfactant? At how high temperatures have micelles been observed ...
CommunityBot
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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 ...
CommunityBot
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4
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1
answer
210
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How can I make an alloy wetter?
I'm trying to make a Bismuth-Indium based low-melt alloy wetter (specifically, better at wetting to solid metals and glass). I've tried adding gallium, which obviously works, but due to its metal-...
CommunityBot
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The entropy change during micellization
I was reviewing the thermodynamics of micelle formation from the Wikipedia page and this book. I understood most of the arguments but micellization is supposed to be an entropy driven process with a ...
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Can micelles form in a polar-vacuum interface?
As the formation of micelles depends on, among many factors, the difference of polarity/relative permittivity of the solvents involved with the surfactant, I'm wondering if a polar-vacuum system is ...
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How can surface excess be negative?
If we have interphase of two phases $\alpha$ (water) and $\beta$ (air), surface excess is defined as
$$\Gamma_i = \frac{n_{i,\mathrm{tot}} - n_{i,\alpha} - n_{i,\beta}} A = \frac{n_{i,\mathrm{int}}} A,...
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2
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Why does magnesium hydroxide solution solidify after passage of time?
I have been trying to make a suspension of magnesium hydroxide in water. Around 40% magnesium hydroxide w/w. Initially it is fluid, but as time passes, it solidifies. What is causing this?
- 30k
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What is the theoretical reason for the dependence of the surface tension on the alcohol concentration in water?
The qualitative sketches I, II and III given
below show the variation of surface tension
with molar concentration of three different
aqueous solutions of$ \ce{ KCl, CH_3 (OH) }$and
$ \ce{CH3(CH2)_{11} ...
- 22.9k
2
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1
answer
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Viscosity at CMC
What happens to viscosity at critical micelle concentration? Does it increase or decrease abruptly, and if so, what's the reason behind it?
I'm aware of changes in other properties such as ...
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How does soap actually reduce surface tension of water
I was a bit confused on how soap reduce surface tension of water.I've read some answers like Why does soap reduce surface tension of water and Why do surfactants lower the surface tension
But the ...
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Thermodynamics of micellisation
Micellisation is found to be spontaneous i.e. $\Delta G < 0.$ It's found that $\Delta S > 0,$ which was intuitive since, solvated molecules are released. And, it may be most loosely started that ...
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What is the logic behind the terminology lyophilic and lyophobic colloids?
Its given in my text book that-
Colloidal dispersions of starch,rubber,proteins etc are lyophilic colloids whereas colloidal dispersions of metals,sulphides etc are lyophobic in nature.
But even ...
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4
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2
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Surface Chemistry - Dipole Moment of Surfactant with Water and Phases of a Monomolecular Layer
Recently, I have been trying to study surface chemistry and I have come across questions that I do not understand how to answer. I understand what a dipole moment is, defined as a charge separation ...
- 22.9k
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1
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718
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How to disperse salicylic acid in sodium lauryl sulfate solution? [closed]
Anti-dandruff shampoo contains salicylic acid as an active ingredient, but when salicylic acid powder comes in contact with a base solution such as sodium laurylsulfate and water (1:3 wt/wt) caking of ...
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9
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1
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Stripeless cleaning of windows
Last week I was discussing with a friend how we thought the stripeless cleaning of windows is achieved when using a cleaner like Windex Glass Cleaner as opposed to just using hot water, in which case ...
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Functionalizing CTAC stabilized nanoparticles
I am working on functionalizing silver-gold bimetallic nanoparticles. My nanoparticles are stabilized by CTAC(cetyltrimethylammonium chloride).The most articles which I found, are about the ...
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What is the surfactant's role in the non-coalescence of water droplets?
I have recently seen many videos that talk about the noncoalescence of water droplets; however, I do not understand the purpose of adding surfactants into the water. From my knowledge (high school), ...
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ordering the hydrophilicity of some polymers
I need to compare the hydrophilicity of those materials to compare contact angles of water with those materials' surfaces for surface tension measurement. Materials are:
PTFE (Teflon), PVC, PS, PVDF, ...
- 10.8k
3
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1
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How do surfactants spread in the case of multiple materials?
For example, consider a pot of water with a drop of oil floating on it, with surfactants present in the water.
Will the surfactants in the water spread evenly across all three interfaces (water/metal,...
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