Unanswered Questions
1,328 questions with no upvoted or accepted answers
13
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Why do alpha-hydroxy ketones respond positively to Tollens', Fehling's, Benedict's, Schiff's and HgCl2 tests?
I learnt from a certain textbook that aldehydes and formic acid respond positively to Tollens', Fehling's, Benedict's, Schiff's and HgCl2 tests.
However, in another textbook I read that even alpha-...
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11
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0
answers
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Role of pH in azo C-coupling reaction, continued
In the question, "What is the role of pH in azo coupling reaction of diazonium with phenol and aniline?" asked by @DhrubaBanerjee and answered by @Klaus-DieterWarzecha, I find several ends ...
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11
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Is there a structured data source containing information on the World Health Organisation's Stability Testing Policies?
Hoping to automate some product testing guidance software, I've been attempting to find a (hopefully live, up-to-date) Database, Web-service, or other structured data source containing the ...
- 6,801
10
votes
1
answer
328
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Why are IUPAC's definitions of exo- and endothermic disconnected from the direction of heat flow?
I'm wondering if anyone can provide a rationale for IUPAC's definitions of exothermic and endothermic since they disconnect these terms from the direction of heat flow.
Specifically, here are IUPAC's ...
CommunityBot
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9
votes
0
answers
263
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Quantitative Transfer of Volatile Standards
(Edited w/ updates) Okay, long story short I work in a lab which has been working on cannabinoid analysis (in the licensed Canadian market) and have had a lot of issues surrounding the standards/...
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9
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0
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215
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How to get defect-energy level diagram from PL data
I am reading this article Phys. Chem. Chem. Phys. , 2011, 13, 14902-14905 and seen that the authors have drawn a image of defect level using PL data
Can you explain me how this diagram can be drawn ...
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9
votes
1
answer
116
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Will the sulfur-iodine cycle and Haber Method work at lower pressures and temperatures?
I have a year-long research project next year in my senior year of high school, in which we have to make some product or prototype to solve some issue.
My interest was in the Liquid Fluoride ...
CommunityBot
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8
votes
0
answers
392
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What exactly is an "electron-sponge"?
What exactly an "electron-sponge" [behavior/action/property/system] nickname is, and what makes a material an "electron-sponge" (preferably, quantitatively)?
From what I found, it's typically a ...
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8
votes
0
answers
102
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Removal of nickel plating on MgB2 without damaging the boride?
I need to remove a nickel plating of a MgB2 wire without causing damage to the MgB2. I felt that electrolysis is the best method but I do not know what electrolyte to use for this. I also need to coat ...
CommunityBot
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8
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0
answers
2k
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Tables/database/literature of specific or optical rotation
I'm looking for a comprehensive reference of experimental specific rotation or optical rotation data. It can be a published literature review, a free web database with API access or one that permits ...
- 43k
7
votes
0
answers
183
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Why does entropy increase in reactions that make more molecules?
I used to understand this (more molecules ⇒ more degrees of freedom), but do no longer, because the total number of atoms is conserved, so translational d.o.f. should just be turned into internal d.o....
7
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0
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200
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Distilling milligram quantities of oil like it's late 1970s
In a currently retracted* manuscript by Tomas Hudlicky [1, Retraction Watch] the following has been noted:
Fifty years ago professors took an active part in all laboratory instructions and they ...
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7
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0
answers
516
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Does phosphoric acid remove stainless steel electropolished layer?
Electropolished stainless steel has a high corrosion resistance due to the oxide film that is created during electropolishing. The film mainly consist of chromium(III) oxide.
Phosphoric acid is ...
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7
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Linear PEI Solution Making
I'm making a solution with linear poly(ethyleneimine) $\ce{[CH2CH2NH]_{n}}$. The bottle indicates that the substance is hygroscopic and must be dealt with under inert gas. Is this really necessary? ...
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6
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How well the conclusion from the "Ignition!" book on rocket fuel science stood the test of time?
There was a wonderful book called "Ignition!" by John D. Clark, published around 1972, very interesting to read. That book covers the history of the rocket fuel development in the middle of ...
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