Unanswered Questions
319 questions with no upvoted or accepted answers
2
votes
0
answers
257
views
Transforming hydroxyl group to carboxylic acid in an aqueous environment
I am looking for a way of converting a hydroxyl group into a carboxyl group in an aqueous environment for eventual coupling to an amine. There seem to be plenty of ways of achieving this in various ...
- 29
2
votes
0
answers
333
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Why does copper(II) sulfate solution turn black on addition of excess sodium borohydride?
In my laboratory experiment, I was supposed to reduce copper(II) sulfate to copper by means of $\ce{NaBH4}$, an indication of which was supposed to be a colour change from blue (copper(II) sulfate) to ...
- 38.4k
2
votes
0
answers
1k
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What is the resulting solution after leaching hardwood ash with water?
After doing online research, I've noticed there are differing interpretations on what happens when ash is mixed with water, so I've come here seeking clarification on what indeed happens, and also ...
- 2,073
2
votes
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answers
49
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Solvent choice in imine formation from quercetin and poly(allylamine)
I am trying to react quercetin and poly(allylamine) to form imine on the repeating units. Poly(allylamine) is dissolved in water. The problem is the choice of solvent. Poly(allylamine) is soluble in ...
- 1,101
2
votes
0
answers
27
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DEG monobutyl ether pH change
We are using DEG monobutyl ether (CAS 112-34-5) in our production. Normally it is pH neutral, however suddenly we noticed that it has shifted to being acidic (pH=3.4).
What has changed in the material?...
- 121
2
votes
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answers
63
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How to model a molecule of benzene surrounded by 100 molecules of water with molecular dynamics?
I have experience calculating molecular properties (mostly DFT). However, I would like to spend some time on molecular dynamics methods. I would like to ask your advice to direct me towards a program ...
- 38.4k
2
votes
0
answers
56
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Calculating the solubility for chromium(III) hydroxide using the complex ion constant
Problem
$$
\begin{align}
\ce{Cr(OH)3(s) &<=> Cr^3+(aq) + 3 OH-(aq)} &\quad K_\mathrm{sp} &= \pu{6.7E-31} \\
\ce{Cr^3+(aq) + 4 OH-(aq) &<=> Cr(OH)4-(aq)} &\quad K_\...
- 38.4k
2
votes
0
answers
173
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Why does sodium citrate in water turn black when blueberries are added?
I recently started making oral rehydration therapy for someone I'm taking care of who developed POTS after COVID-19 infection. (ORT was recommended by their doctor.) I use the standard ingredients of ...
- 29
2
votes
0
answers
78
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Colligative properties: why does the size of solute not matter?
Colligative properties are defined as the "properties of solutions that depend on the ratio of the number of solute particles to the number of solvent molecules in a solution, and not on the ...
- 31
2
votes
0
answers
140
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Permanent ink from urethane, 99% IPA, and pigment?
I’m an artist and I started working with recycled plastic bottles as a material recently. I want to paint the plastic and retain its transparency, but acrylic paint won’t stick without priming and ...
- 21
2
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38
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Isomerization of phosphorylated 2-imino-1,3-dioxalanes into phosphorylated cyclic carbamates
I found a patent dating back to the Soviet Union. The patent number is 256764, and the patent describes the synthesis of phosphorylated cyclic carbamates. Here is a section of the patent, followed by ...
- 1,264
2
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0
answers
125
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Which salts precipitate from a potassium/sodium chloride/sulfate solution?
This is not a homework question. I am not in any course of study. The following question arises from my personal curiosity. If 1 mole of sodium sulfate and 2 moles of potassium chloride are dissolved ...
- 38.4k
2
votes
0
answers
408
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Effect of charge density on electrolysis of dilute sulphuric acid
I am told that if electrolysis of dilute sulfuric acid is performed under high charge density, then the following reaction takes place at anode instead of evolving oxygen:
$$\ce{2 HSO4- -> H2S2O8 +...
- 38.4k
2
votes
0
answers
283
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What are common solvent removal methods?
In a laboratory setting, the most common solvent removal method is rotary vacuum distillation. This is something I have performed many times, starting in organic chemistry labs. However, I am ...
- 44.3k
2
votes
0
answers
150
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Competing half reactions in electrolysis of aqueous solution of sodium hydroxide
If you run a direct current using pure nickel electrodes through a solution of NaOH in distilled water, you will separate the water into hydrogen and oxygen.
Are there any other reactions that could ...
- 38.4k