Unanswered Questions
518 questions with no upvoted or accepted answers
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Which potentials are suitable for molecular dynamics simulation of simple explicit solvents?
Which potentials (force fields) are suitable for adequately simulating (mixtures of) explicit solvents? Interesting rheological properties include viscosity, surface tension, heat capacity.
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Cobalt Chloride in various solvent/water mixtures - tested
In a recent post the solvatochromic behaviour of cobalt chloride in acetone was discussed. There were some ideas how the acetone might influence the ratio between the blue $\ce{[CoCl4]^2-}$ and the ...
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How does (E)CA glue ("super glue", "crazy glue", etc.) cure?
I use CA glue† very frequently in my shop, but I'm not entirely sure how it works. I've noticed three main modes of curing, I've emphasized the key observations:
When dispensed, it will remain fluid ...
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Do "random" "2D" polymers constrained to a box actually form "space filling" curves?
Background: The self avoiding walk model is (allegedly) a reasonable model for polymers, at least with respect to certain "universal" (i.e. lattice independent) constants -- see section 1.1. in this ...
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Are all humectants sticky?
While using a topical lotion based on ethanol, water and propylene glycol, I noticed that it becomes sticky while drying. Propylene glycol is a humectant and is used for this purpose in ...
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Why is the rubber tip of my capacitive stylus no longer conductive?
In 2014, so eight years ago, I bought five styluses from China. Cheap stuff obviously. They worked fine while I used them, but soon after they were just left in a drawer. Last night I realized that ...
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Why is supersaturated sodium acetate so (meta)stable?
Sodium acetate is a common example used in general chemistry lectures to illustrate the idea of supersaturation, and that precipitation of a supersaturated solution can be initiated by a seed crystal. ...
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Thermophysical properties of liquid Galden LS 230 between 25 °C and 230 °C
I'm looking for thermophysical properties of Galden LS 230, a liquid polymer (PFPE) produced by Solvay (https://www.solvay.com/en/markets-and-products/featured-products/Galden.html) at temperatures ...
CommunityBot
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How can copper(II) sulfate crystallize outside a glass vial?
I'm making copper sulfate crystals in glasses. Within a few weeks, the copper sulfate seems to crystallize both inside and outside the glass:
(A few weeks after making a new solution)
(Yet another ...
- 17.5k
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Dissolving ability of octane vs nonane on neoprene
I have been working with straight chain octane and nonane. The neoprene seals in some parts of the apparatus are allegedly far more vulnerable to the deleterious effects of octane than nonane - why? [...
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How to dissolve a strong resin in difficult situation?
The resin is made up from two components:
Component A: silicic acid, sodium salt (less than 10% sodium silicate)
Component B: Diphenylmethane-4,4'-Diisocyanate, isomers and homologs (MDI,Polymer-MDI)...
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Dependence of elasticity on temperature and degree of vulcanization of typical commercial rubber band
I am doing a school experiment that tries to find how the elasticity of rubber band depends on temperature.
From all the research I have done, theory suggests stress to increase linearly with ...
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Oxygen tolerant RAFT polymerization using AIBN?
I want to do some RAFT polymerizations but don't have a nitrogen line at the moment. It seems that people have recently implemented oxygen scavenging strategies to enable open-air RAFT polymerization. ...
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What pH value of 1M sodium crotonate solution supposed to be?
I need to prepare the $\pu{1M}$ solution of sodium crotonate, however, I don't have one in lab, but I do have sodium hydroxide and crotonic acid.
Thus, I calculated that for $\pu{100 mL}$ of $\pu{1M}$ ...
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What determines 3D printing material compatibility?
3D printing, specifically the type common for consumers FDM or FFF, involves laying down thin (typically 0.1 to 0.2mm) layers of molten plastic. Modern consumer printers can use various filaments: PLA,...
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