Unanswered Questions
319 questions with no upvoted or accepted answers
3
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Can there be an aqueous solution with a convex meniscus?
This question is motivated by a quote from a TV show:
A detective is looking at a small vial (really a glass tube) that supposedly contains poison. Then the detective says:
You don't have to take AP ...
- 131
3
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0
answers
1k
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Number of moles of acidified potassium dichromate required to liberate 6 moles of iodine from an aqueous solution of iodate ions
I came across this question in a recent exam I had taken:
How many moles of acidified $\ce{K2Cr2O7}$ is required to liberate 6 moles of $\ce{I2}$ from an aqueous solution of $\ce{I-}$ ?
So this is ...
- 426
3
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497
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The most convenient process to purify Oxalic Acid up to a high level of purity
I am set out to purify a batch of commercial oxalic acid with the aim in mind to end up with a highly pure product (starting from $\pu{4,000 ppm}$ total impurities and doing so with basic lab ...
3
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0
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116
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Molar ratios not leading to complete reaction in Schweizer's reagent production
In my home lab, I've reacted $\ce{Cu(OH)2}$ with aqueous ammonia to produce Schweizer's reagent. However, I'm surprised by the amount of ammonia required to react with this amount of $\ce{Cu(OH)2}$. ...
- 139
3
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495
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Acetic Acid type of solvent
I want to ask a question about polar/non-polar (a)protic solvents.
The following information was given to me in the lecture hall today regarding solvents in organic chemistry.
I recall the ...
- 1,230
3
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708
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What pH indicators are commonly used for non-polar medium?
Compounds, commonly used as pH-indicators, are soluble in aqueous media and polar solvents (DMSO, DMF, NMP etc.) and are functional pretty much across all these solvents. However, practically none ...
- 38.4k
3
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157
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Removing Tungsten Trioxide from Tungsten Electrode
I need a very sharp tungsten electrode, and I think radial electrochemical etching with sodium hydroxide is the way to go. The problem therein (I think) is that the etching will cause an oxide layer ...
- 38.4k
3
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1k
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Calculating total volume mixing NaCl and water
I'm (as a non chemist) trying to calculate the the volume of a NaCl solution. The problem is that I know the volume of water prior to mixing in NaCl, but I want to know the volume of the solution ...
- 3,316
3
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160
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Chemistry Behind TMOS Aerogel
I have found out how to make silica aerogel.
Currently, the solution that I need to create to make the gel requires tetramethyl orthosilicate or TMOS. Furthermore, the procedure requires me to make ...
- 131
3
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342
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Hydrogen Peroxide Heat of Dilution
Based on some data here, I am getting the heat of dilution of 100% $\ce{H2O2}$ as approx. 1100 cal/mole.
That's about 4.6 kJ/mol if I did my math right.
Is this a correct value? Seems too low to ...
- 17.6k
3
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84
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Can the directionality of an SN2 reaction depend on solvent polarity?
Because of the effects of solvation, halide ions have differing nucleophilicity in protic solvents vs aprotic solvents, iodide being the best nucleophile in protic solvents and fluoride being best in ...
- 71.6k
3
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0
answers
110
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Poor aqueous solubility of chloroazodin
Below is the structure of chloroazodin:
Why is chloroazodin poorly soluble in water? It has multiple amine and imine nitrogens, all of which appear to be available for hydrogen bonding, and thus it ...
- 147
3
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391
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Solvent for Norland Optical Adhesive
I'd like to know if there is any solvent that dissolves Norland Optical Adhesive 65 (and Rhodamine 6G), but does not dissolve PMMA that is used in e-beam lithography.
I've tried acetone, methanol, ...
- 38.4k
3
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1k
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Why anhydrous acetic acid is differentiating solvent?
Anhydrous acetic acid is differentiating solvent in which strong acids show different strength but water isn't. Why anhydrous acetic acid shows the strength of acids clearly, but water solvent cannot ...
- 4,606
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80
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Can a brine water electrolysis be looped?
Electrolysis of brine yields hydrogen and chlorine gases and aqueous $\ce{NaOH}$. So is it possible to combine the gases to form $\ce{HCl}$ gas, and mix it back with the aqueous $\ce{NaOH}$, so it ...
