Unanswered Questions
8,724 questions with no upvoted or accepted answers
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[Zn(edta)]2- optical activity?
hey guys this is my first time asking a question on stack exchange so not really sure about the format but here's my attempt
[Zn(edta)]2-
So in this compound the ligand EDTA is apparently optically ...
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NMR pulse sequence for precise measurements of coupling constants?
The usual procedure for measuring $J$ coupling constants in NMR is to record a 1D spectrum and estimate the constant from the differences of peak frequencies. Fitting the spectrum to a lineshape ...
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How to interpret molecular orbital (HOMO - LUMO) plots in Chem3D 22.0?
Recently, I have been trying to understand the origin of the difference in reactivity of alkynyl-boron(ate) complexes so I tried to generate a molecular orbital plot on Chem3D (Version 22.0.22 64bit) ...
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Mechanism for formation of both Iron (III) Oxides in rust equation?
In the equation
$4 \mathrm{Fe}^{2+}(a q)+\mathrm{O}_2(g)+(2+4 x) H_ 2 \mathrm{O} \rightarrow 2 \mathrm{Fe}_ 2 \mathrm{O}_ 3 \cdot x H_ 2 O+4 \mathrm{H}^{+}(a q)$
I'd like to know how both the Iron (...
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Stability of carbenes
For predicting the order of formation of carbenes from the following compounds (CHI3, CHBr3, CHF3), we can take a look at the stability of the halide anion that is formed (I- vs. Br- vs. F-) and the ...
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Breaking of halonium ion in unsymmetrical alkanes
So what i have learnt is that breaking of halonium ring follows partial sn1 sn2 reaction. in that the carbon where partial positive charge is more stable is attacked. my doubt is for checking the ...
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Irreversible uncharged acid/base indicator
I am conducting a process in an electrochemical cell where at the cathode or anode surface the pH might be acidic or basic. To figure out if either one is correct I would like to find a reaction that ...
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Precessional frequency in H-NMR
Suppose we have a hydrogen nucleus. Now, let's apply an external magnetic field $B$. As the magnetic field is applied, the hydrogen nucleus undergoes precessional motion about its own axis with ...
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Why do we assume that entropy of H+ ion solution at 298 K is zero?
If we assume that entropy of H+ ion solution at 298 K is zero, then the entropy of other solutions which have less entropy than H+ will have negative entropy.
But entropy is defined as the amount of ...
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Why DMSO has much higher freezing point than DMF (19 °C vs -61 °C)?
Recently, while solvent optimization of a reaction, I found DMSO froze in an ice-bath but DMF didn't.
From Wikipedia, I found out that DMSO (dimethyl sulfoxide) has a freezing point of 19 °C (ref. 1) ...
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What is the Best Transition State Search Method
I want to find transition states (TS) on the potential energy surface (PES) of small/medium reactions with sinle-ended methods. For example the reaction network from here. I've been looking at ...
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Gaussian Program Error for Linear Triatomic Molecule
I am trying to calculate the Hessian and vibrational frequencies of OCS (and eventually some anharmonic properties) with Gaussian09. However, the program always fails and I end up with the following ...
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Sodium zincate reaction
does adding zinc chloride into the solution of sodium zincate formed by the reaction of zinc chloride and excess of sodium hydroxide form the precipitate of zinc hydroxide ? I mean does sodium zincate ...
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Reaction of ethyne cyclohexane with excess of hydrogen bromide
I have a question in my chemistry workbook, and the solution to the question is different from what I think it is.
The question is what is the product of the reaction between 1-cyclohexyl-1-propyne ...
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Why is silicon dioxide a network solid while sulfur dioxide is a molecular gas
In my understanding sulfur dioxide’s Lewis structure has one lone pair on the centre atom (sulfur) with one pi bond to each oxygen atom, while silicon cannot form these silicon-oxygen pi bonds. Both ...
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