Unanswered Questions
8,738 questions with no upvoted or accepted answers
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The Krieger-Li-Iafrate Approximation
I am having trouble understanding what KLI approximation is. Could someone explain it to me in an intuitive/simple way?
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9
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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 ...
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Order of Basicity of Nitrogen Trihalides
I was asked to arrange nitrogen tri-halides in order of increasing basicity. On looking up the answer online, it turned out to be the following: $\ce{NF3}$ < $\ce{NCl3}$ < $\ce{NBr3}$ < $\ce{...
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Mysterious violet-purple compound in "Gerber Method" & "Banana oil synthesis"
During the determination of fat in milk (Gerber method), in a milk butyrometer are mixed milk + $\ce{H2SO4}$ 90% w/w + isoamyl alcohol (isopentyl alcohol) and heating.
The acidic mixture separates ...
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Why is octaoxygen diamagnetic?
I tried considering that according to LCAO-MO theory $\ce{O2}$ is paramagnetic, which is confirmed by experimental evidence. Since octaoxygen has the crystal structure in figure, I thought there is a ...
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Alcohol to Ketone by CrO3 in cyclohexane
I have encountered an exercise question on conformation of cyclohexane and there is a statement saying, 'converting alcohol to ketone by CrO3 is much faster when R-OH is in axial position'. I would ...
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Do all α-hydroxy ketones give Tollens’ test?
It is well known that terminal α-hydroxy ketones give Tollens’ test, via tautomerisation. Also, α-hydroxy ketones flanked by aromatic groups give Tollens’ test, such as benzoin.
But do all α-hydroxy ...
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Mechanism of Hypervalent Iodine Phenolic Coupling
I need some help understanding the hypervalent iodine phenolic coupling reaction taking place in this synthesis of morphine, the reaction uses $\ce{PhI(OAc)2}$ as the hypervalent reagent and ...
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Why does a sealed plastic bag of dish soap, water and air expand when shaken?
I've noticed that when I put dish soap, water and a little air into a sealed plastic bag, and then shake the mixture, it forms soap suds and the bag expands significantly in volume. Why does it expand?...
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What are the limitations of the Born-Lande' equation?
The Born-Lande' equation is used to theoretically calculate the lattice energy, $\Delta U$, of ionic compounds. It is often cited as such in literature,
$$\Delta U = -\frac{k_Az_1z_2Me^2}{4 \pi \...
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DIY hand sanitiser solution forms spongy substance
I am trying to make my own hand sanitiser since it’s sold out everywhere. The formula I use is 1 part aloe vera gel in 2 parts 100% isopropyl alcohol. The problem is when mixing the two, the solution ...
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Are primitive GTOs normalised before contraction, or is the resultant basis function normalised afterwards?
I'm quite curious about this:
In a basis set (I'll just use minimal-basis STO-nG basis sets for convenience), the basis functions are written as a linear combination of primitive GTOs. Are the GTOs ...
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Does water really have strong EM absorption at 3 kHz in solid and 2 GHz in liquid? Why the huge shift?
While writing this answer to the question Transmitter receiver coil separation for Electromagnetic Terrain Conductivity Measurement I ran across this large PDF file of a book Soil and Environmental ...
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Effect of spontaneous transmutation of atom in crystal
What happens to a compound when one of its atoms changes via spontaneous nuclear reaction to an atom with very different bonding? For example, beryllium-7 turns into lithium-7 with a half-life of 53 ...
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The carbon-13 chemical shift of acyl chlorides vs ketones
In lectures, we were taught that ketones and aldehydes tend to have chemical shifts of around 200 ppm, while acid derivatives (carboxylic acids esters etc) tend to have values around 160–170 ppm.
The ...
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