Questions tagged [experimental-chemistry]
This tag should be applied to questions relating to the theory, design, techniques or performance of chemical experiments. This includes but is not limited to theoretical structures, expected products, thermal calculations, and empirical analysis. Additional tags should be applied to narrow down the field of research.
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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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Cooling a 100°C beaker in cold water
In my nanoparticle synthesis, I need to cool a beaker with boiling solution (50mL beaker) rapidly to arrest a reaction at a specific size of nanoparticle. Letting the hot beaker cool passively is too ...
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How to avoid side reactions when making boronic esters (Homocoupling, Hydrogen specie)?
I have been working with suzuki couplings using substituted naphtalenes (typically 2-bromo-7-R-naphtalene) for a while now, and making the boronic specie is always a pain.
I can't make the boronic ...
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Will a nitro aryl resist an halogen exchange using nBuLi?
I would like to boronate 2-bromo-6-nitro-naphtalene using nBuLi and quenching with 2-Isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane. Since there is no alpha proton to the nitro, and that the nitro ...
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After adding the electrophile (BOMe3) in an halogen exchange (nBuLi) reaction, why do we leave the reaction stir overnight?
Very basic question.
In all the procedures for halogen exchange reactions reported using boronic compounds, the reaction is left to run ON at room temperature after addition of the boronic specie.
In ...
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How to quantify the concentration of sodium nitrate leftover from eutrophication through titration?
In my experiment, I am trying to quantify the nitrate absorption by duckweed. I need a titration method to measure the left over nitrate levels in the solution. However, this is to be done in a school ...
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Brilliant fluorescent properties of Na2S(x) obtained from Na2SO3 or Na2S2O3
When $\ce{K2SO3}$ or $\ce{Na2SO3}$ is heated strongly by any method (in a flame, in an electric arc, on a metal plate in an induction heater), the resulting residue should be a mixture of $\ce{Na2SO4/...
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Fundamental reasons for using vapors for ALD rather than solutions
Atomic layer deposition (ALD) has been developed for many materials, as can be seen from this overview: https://atomiclimits.com/alddatabase/
However, a search for liquid phase ALD gives less results.
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What role does CaCl2 play in a gelation medium?
To produce sodium alginate beads coated with chitosan, following procedure was undertaken:
Sodium alginate was dissolved in distilled water at a concentration of 4% (...) The gelation medium was ...
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Comparing calculated DOS with experimental valence band spectra for oxidized platinum nanoparticles
I've been studying the electronic structure of platinum nanoparticles using DFT and have a question about comparing my calculated density of states (DOS) with experimental valence band spectra.
I ...
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Standardizing alkaline ferricyanide solution [closed]
The ferricyanide method of determining reducing sugars is simple but I need clarity on time of addition of potassium iodide solution. I am unable to observe change in color from yellow to blue. I even ...
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What does the blue square on a volumetric flask mean?
What does this blue square on my volumetric flask mean? I see such squares/rectangles on a numerous other flask brands as well. What is its purpose?
user146152
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Percentage Yield
For the above MCQ question, I took the equation to be
$$\ce{CaC2 + 2H2O -> C2H2 + Ca(OH)2}$$
I then calculated the moles of $\ce{CaC2}$ as 0.7273 moles, which has a 1:1 molar ratio to $\ce{C2H2}$, ...
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How does a conc. electrolyte solution extract water from a organic phase like diethyl ether or ethyl acetate?
In organic chemistry, often, during the last steps of a workup we use concentrated brine solution (NaCl) to "extract" the water from the organic layer, especially when we have an organic ...
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Is nitroglycerin synthesis within human digestive system from eating soap possible?
Could you make nitroglycerin by eating large quantities of pure glycerine soap? A quick google search told me flatus are 59% nitrogen, but I couldn't find anyone else with my exact question (which ...
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