All Questions
45,375
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Can Gibbs Free Energy equation be used to explain why some phase changes are exothermic or endothermic?
I was wondering about some ways to explain why some phase changes are exo / endo.
I am aware that for endothermic phase changes (boiling, melting, sublimation) energy input is required to raise the ...
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23
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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 ...
-4
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determine the percentage of nitrogen Amide nitrgen - Nitrate nitrogen - organic nitrogen [closed]
Is there a way to determine the percentage of nitrogen according to its source using the Kjeldahl device?
Amide nitrgen - Nitrate nitrogen - organic nitrogen
4
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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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off-resonance Raman and normal Raman spectra [closed]
What is the difference between the off-resonance Raman and normal Raman spectra in gaussian? How to calculate the off-resonance Raman spectra in gaussian?
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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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Why does chlorine have a higher electron affinity value than fluorine? [duplicate]
Why does chlorine have a higher electron affinity value than fluorine? Since this periodic property tends from the bottom up (in the group), the logic would be that the fluorine is the element with ...
2
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23
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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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2
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75
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Why would the theoretical pH not match the measured pH when performing a titration of NH4OH with HCl?
I ran a weak base - strong acid titration experiment using an automatic titrator. I started with an aqueous ammonia stock solution (somewhere in the range of 0.1 - 2.5 wt.%) that was left open to ...
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1
answer
110
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Converting cif file with powdll, plotting cif file in excel
When I press convert in powdll converter software, I get this error message "Object reference not set to an instance of an object". I haven't been able to convert any kind of file type ...
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24
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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 ...
-1
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2
answers
68
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What are the units of equation 13 of Buckingham's 1960 paper about chemical shift influenced by electric field?
Has anyone read Buckingham's 1960 paper 'CHEMICAL SHIFTS IN THE NUCLEAR MAGNETIC RESONANCE SPECTRA OF MOLECULES CONTAINING POLAR GROUPS'? I'm having trouble understanding Equation 13 regarding the ...
- 25
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22
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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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How do carbonyl compounds react with conc.H2SO4? [closed]
Does condensation take place always? If not what are the exceptional cases?
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