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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Why cool a reaction down when adding reagents if you're only going to reflux subsequently?
I've seen several procedures using thionyl chloride (SOCl2) to make an ester, where the first step is to add the thionyl chloride to the reagent/solvent on ice or subzero temperature, followed ...
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Trends in pKb for both acetic acid and water
I am trying to rationalise a result that I have recently measured in the lab. I'm measuring the pKb of different compounds in anhydrous acetic acid, using the procedure outlined in this paper (https://...
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About whitish layer that formed on chocolate bar
I noticed a whitish layer on the surface of a chocolate bar that I ate yesterday. I looked at the pack where it was mentioned that,
"Temperature and humidity changes may cause product to develop ...
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What precipitate is formed when a copper coin is dissolved in concentrated nitric acid?
The method being used.
I am currently carrying out a school project where I am determining the copper content of 1p coins. The coins used are British 1 pence coins dated before 1992 as after this year ...
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What could be used to thicken Ferric Chloride solution?
I'm curious if it's possible to thicken Ferric Chloride so I can control it more on a less than horizontal surface ?
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Calculate percent composition from XPS?
I have an XPS graph and was wondering how to calculate percent composition. I do have the percent compositions that were determined from the graph, but I don't know how they were found. For reference, ...
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Testing whether an unknown powder is wheat gluten (at home)?
Last week, I ordered wheat gluten to make seitan. I received some powder and attempted a recipe, which mixes 100g of water with 100g of gluten to form a sticky dough. However in my case, I only got a ...
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Oxidation of Isopropanol by Permanganate in Basic Solution
so I've been designing an experiment where I will explore the effect of isopropanol concentration on the colour change of a solution containing permanganate, isopropanol, and NaOH.
I know that the ...
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How can I refine my method of determining iron content in spinach?
I have begun a chemistry experiment that attempts to determine how iron content in spinach is affected by the length of time it is cooked. Through research, I learned that iron content is often ...
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Question about the differences of white and grey NaH properties
We are having some problems with the next reaction in our lab. As you can see, is the sulfonylation of an indole in which we use NaH (60% dispersion in mineral oil) as a base. This reaction goes with ...
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How to remove hexane from nBuLi
As described in a paper, the authors removed the hexane from the nBuLi solution "under reduced pressure".
I was wondering if anyone had any experience on how to proceed safely with this ...
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Some particles are observed inside the wall of glass vial
Recently, when I use glass vial, some particles are observed inside the wall. These particles are so small and transparent or maybe white-colored, so it is hard to observe during ordinary usage. But ...
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Volumetric flow rate ratio calculation
I'm using two tanks of nitrogen and oxygen and mixing them in different ratios to change the oxygen partial pressure in the system. System is opened to the atmosphere through the venting pipe which ...
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What determines the pressure in the system when the gas tanks are opened?
I have two gas tanks of nitrogen and oxygen. Mixture of gases is created at specified composition and used in the system of interest.
Let's say I want to create an atmospheric conditions in my system, ...
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Could I expect any adverse reactions with this ink mix?
Our newest R&D project for a permanent, outdoor ink includes:
$\pu{25 g}$ of solvent blue 70.
$\pu{25 g}$ of nigrosene.
$\pu{??? g}$ of silver nitrate in a denatured alcohol base.
Several "...