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Author: Subject: Polarity of methanol
Morgan
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[*] posted on 14-9-2021 at 15:15
Polarity of methanol


From this table the relative polarity of methanol is around .762 and water 1. Acetone is listed at .355.
https://sites.google.com/site/miller00828/in/solvent-polarit...

Another one states a polarity index of 5.1 for methanol and water 10.2. And acetone is exactly the same as methanol, 5.1.
https://people.chem.umass.edu/xray/solvent.html

Polarity of Solvents In ascending order, water the highest.
Water
Acetic Acid
Ethyleneglycol
Methanol
Ethanol
Isopropanol
Pyridine
Acetonitrile
Nitromethane
Diehylamine
Aniline
Dimethylsulfoxide
Ethylacetate
Dioxane
Acetone
Dicholoroethane
Tetrahydrofuran
Dicholoromethane
Chloroform
Diethylether
Benzene
Toluene
Xylene
Carbontetrachloride
Cyclohexane
Petroleum ether
Hexane
Pentane

I was thinking about substituting methanol for water in a Lord Kelvin Water dropper experiment and wanted to understand what's what with these numbers or how to estimate the relative electrostatic properties.
Here is an example of acetone bending to an ebonite rod rubbed with rabbit fur.
https://youtu.be/aPVwOtDEp5k
And kids having real fun with water, acetone, and hexane
https://youtu.be/D2R4ccyvclM

What might be pretty if workable would be to get this simple interesting effect seen below going using methanol and view the drops on fire orbiting an oppositely charged body. One fire stream from the droppers could be colored red with lithium chloride and the other boric acid green.
https://youtu.be/D1u5YL2afT4
The effect in space from NASA using a knitting needle
https://youtu.be/qHrBhgwq__Q







[Edited on 14-9-2021 by Morgan]
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[*] posted on 15-9-2021 at 04:33


I don't think there is any relationship between molecular polarity and bulk electric charge. The main difference would be the conductivity of the different liquids.
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Metacelsus
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[*] posted on 15-9-2021 at 05:28


Also, using flammable solvents in an environment designed to generate static electricity may be a bad idea.



As below, so above.
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Morgan
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[*] posted on 15-9-2021 at 16:02


I wonder if this is a fair partial summation?
"Qualitatively, polar solvents promote the separation of solute moieties with unlike charges and they make it posssible for solute moieties with like charges to approach each other more closely. Like the concept of electronegativity, the more precise you want the definition of polarity, the harder it is to define. Polarity is thus a ILLDEFINED TERM."
" It covers the solvent's overall solvation capability (solvation power) for solutes. The polarity depends on the action of all possible, nonspecific and specific, intermolecular interactions between solute ions or molecules and solvent molecules. It covers electrostatic, directional, inductive, dispersion, and charge-transfer forces, as well as hydrogen bonding forces, but excludes interactions leading to definite chemical alterations of the ions or molecules of the solute."
https://www.thevespiary.org/talk/index.php?topic=11222.0
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Morgan
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[*] posted on 15-9-2021 at 16:32


Quote: Originally posted by Metacelsus  
Also, using flammable solvents in an environment designed to generate static electricity may be a bad idea.


I'm planning on using capillary sized drops of methanol from an isolated 50 ml tank, using fused quartz over a large metal dish. It's proving hard to keep the design elegant while figuring out how to hold and support the parts without a lot of kludge.
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Morgan
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[*] posted on 16-9-2021 at 03:31


I found this video of the effect I'm interested in with methanol, and thus my plan for substituting it for water in a Kelvin water dropper. A little after the 5 minute mark you can see how responsive methanol is. And for whatever reason the deflection from the charged pvc pipe rubbed with wool is seemingly even more pronounced than with water in one particular attempt if you watch the comparisons a few times. Whatever the case, and even though water is the more polar molecule, the attraction appears sufficient for my purposes.
https://youtu.be/oo0niY3LCA8

[Edited on 16-9-2021 by Morgan]
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[*] posted on 16-9-2021 at 06:32


This has got me thinking. Does the plate of a charged capacitor contain ions? When charged up, one side has more electrons and the other has less. But I can't imagine the metal actually becomes ionized, does it? What is the atomic nature of voltage?
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