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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Is this evidence that solubility of sodium bicarbonate<sodium carbonate?
Someone introduced $\ce{CO2}$ into saturated $\ce{Na2CO3}$ solution, and observed that white precipitate is produced. He therefore claims that $\ce{NaHCO3}$ has less solubility than $\ce{Na2CO3}$.
His ...
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Does manganese dioxide disperse differently in bases than in water?
As part of a project in uni I've been given a task in my chemistry laboratory to synthesise manganese dioxide powders.
I prepared a precipitate of it by reacting manganese chloride with sodium ...
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Surface treatment and current density: electrodeposition of Cd and Ag
I'm currently working on a cadmium and silver electrodeposition project.
Let me explain:
I'm doing electrolytic surface treatment on low-alloy steels as well as stainless steels. At present, we have ...
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Is it possible to create a solid from PVDF solution?
I am working on a project where I am attempting to line an aluminium tube with PVDF. The finished wall thickness is required to be 4mm thick.
I have investigated such processes as injection moulding ...
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The log K value for Cr-EDTA complex is 23, still Cr(III) cannot be titrated directly [closed]
It's related to stability constants.
I don't get the question and where is it taking and wanting to answer.
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What precipitate forms when adding aqueous sodium sulfate solution to an unknown white solid?
I don't understand why there aren't two solutions to the following problem:
You are presented with a white solid and told that due to careless labeling it is not clear if the substance is barium ...
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Assignment of NMR peaks of polystyrene
I’m having trouble identifying the peak around 3,75 ppm in the 1H-NMR spectrum of polystyrene measured at 400 Hz in CDCl3. Could someone please provide their perspective on it? I see it appear in a ...
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Schlenk line simultaneously opening vacuum and gas
I’ve been working in the lab for some time now, but I’ve found conflicting information when asking this question, so maybe you know the answer.
When working in a Schlenk line with double oblique ...
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Should I remove inhibitor from methyl acrylate?
I need to run multiple aza-Michael additions of methyl acrylate with various amines (dimethylamine, benzylamine, phenylethylamine, aniline, etc.) in order to get the bis-ester. I was wondering if the ...
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Largest molecules verified in a Miller Urey experiment
What are the largest molecules confirmed with confidence in a Miller Urey experiment?
I know the experiment can create amino acids (which are mostly <250Da) and nucleotides (which are mostly <...
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visualization problem of dilution of enthalpy $\Delta_{dil} H$ data with different initial concentrations
description
I have a question about the $m_f$ vs. $\Delta_{\text{dil}} H$ plot in some experimental studies.
For example, the dilution-of-enthalpy data at 300 °C with two initial concetration ($m_i$) ...
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Using potassium thiosulfate instead of sodium thiosulfate in iodine clock reaction
I am familiar with the iodine clock reaction that uses sodium thiosulphate. Still, I'm wondering if I could use potassium thiosulphate instead, as it's the thiosulfate that reduces the Iodine.
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What is laboratory air?
Oftentimes in the literature, particularly for oxidation studies, the authors mention that experiments were performed in "laboratory air." Is there any distinction from laboratory air from ...
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How to identify salts using mutual reactions
There are ten test tubes in the rack at your disposal (1 – 10) and each test tube contains one of the aqueous solutions of the following salts: $\ce{Na2SO4, AgNO3, KI, Ba(OH)2, NH4Cl, Ag2SO4, Pb(NO3)2,...
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Why potassium carbonate breaks glass when heated? [closed]
I have been studying about desiccants for a while and testing some inorganic salts, including calcium chloride, sodium sulfate and potassium carbonate. When they get enough moisture from air, I ...
