Questions tagged [separation-techniques]
For questions about the separation of mixtures and solutions into pure compounds
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What is the function of thin layer in thin layer chromatography?
I just learned about the thin layer chromatography, which I think is basically the same as the paper chromatography.
I am wondering what is the function of the thin layer? I mean, what's special about ...
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How can I separate these two alcohols from each other out of the aqueous solution?
I have the following question for homework and am stumped. I am tasked with separating 3-(2-methoxyphenoxy)propane-1,2-diol and (1R,2S)-2-(methylamino)-1-phenylpropan-1-ol. They are both solvated in ...
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Can separated and purified substances be obtained from a chromatogram?
I am studying chemistry, and I am learning about chromatography.
But I am confused about how chromatography is used to ‘separate and purify’ substances.
I have learnt about chromatography paper, ...
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How do you get contents of large flask into a smaller separatory funnel?
Separatory flasks that I use have a ground glass joint, but it is not clear how that joint is to be used. Videos I have seen just show people pouring stuff into the throat of the funnel.
Normally the ...
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Why does a molecular sieve work for gas separation?
I was looking at membrane separation of air to nitrogen / oxygen and saw some details on the molecular sieve which on Wikipedia states you can get much higher purity from an adsorber / sieve, but when ...
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How does industry separate glucose from fructose using liquid chromatography when producing high-fructose corn syrup?
Can someone explain how the separation of glucose and fructose is achieved using liquid chromatography in the industrial production of high-fructose corn syrup?
I've seen references to ion-exchange ...
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How does a freeze-thaw cycle separate a mixture?
Imagine that I defrost a tube of serum (only the yellow stuff, with blood cells removed) standing still and upright in ambient air. I have seen that as it defrosts the sample separates into different ...
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Theoretical plates in Plate theory of chromatography
In "Chromatography theory" by Scott and Cazes,
The plate volume is given as ($v_m+Kv_s$) where $v_m$ and $v_s$ are the volume of stationary and mobile phase in the column and $K$ is the ...
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How to store small amounts of gas
I need to store small amounts of gas. I already saw devices that look similar to the image below, but I don't know how they are called. Does someone here know how these devices are called? I am also ...
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My particles won’t separate without neutralizing the solution. I want to understand why?
I etched active carbon with a concentrated KOH solution and added HCl to neutralize the KOH. Separeted the particles with centrifuge at 4000 rpm. They should be micron sized.
My boss asked me to stop ...
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Steam distillation vs fractional distillation
I am a high school student and I am a little confused in the techniques used to purify organic compounds. For example, in steam distillation we reduce the external pressure on the compound to be ...
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are refractometers generic?
I need to check the presence (and also purity approx) of a substance in solution. I have a very good reference (10mg/1ml - the substance in water).
Can I use a refractometer to do this?
I am trying to ...
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Protein purification pressure limits confusion, about the X-MPa limit for FPLC?
I have always been a bit confused about column pressure limits. I have to elaborate a bit on the problem to get to my question:
In protein purification we use the äkta purification machines (e.g. ...
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Removing chloride ions from humic acid purification
I used HF and HCl in humic acid purification, and now I need to remove the Cl ions from solution. What should I do to remove the Cl ions? Do I just wash it with distilled water, or is there another ...
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Why does a big protein move during gel electrophoresis but to a lesses extent through a size exclusion column?
A big protein going through gel electrophoresis will be forced through the gel, it will drift a small way and will show on the top of the gel, while in size exclusion, the big protein is not forced to ...
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How to separate a racemic mixture of 1,2-diols
[upjohn dihydroxylation]2I want to ask that i synthesise R-substituted-1,2-Diol with (ee=1:1) ratio of R-, S- with the help of Upjohn Dihydroxylation. i try to seprate it by different mobile phasese ...
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What matters for ion exchange: net or local charge?
I am interested in separating two small organic molecules by ion exchange chromatography.
Following the example set by several old papers for these molecules, I want to use a cation exchanger. Both ...
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How to separate the salts within homemade sea salt
Goals
There are a few things that I'm looking to do:
Separate salt from seawater via some evaporation technique.
Separate the each of the major salts from the resulting sea water to get each into ...
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Calculation of the Seperation factor of Ethanol / Water rectification based on two saturated vapor temperatures
I want to calculate the efficacy of a Water / Ethanol rectification based on two temperatures with help of a vapor-liquid equilibration diagram.
The first temperature is measured right above the ...
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How to remove oil/grease contaminant from an aqueous solution?
I have a solution of water and calcium nitrate that is contaminated with some sort of heavy petroleum oil, semi-solid at room temperature a bit like petroleum jelly, and a strong odor of very crude ...
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Dynamic viscosity of gas mixture (appropriate estimation)
What estimation of the dynamic viscosity $\eta = f(T)$ $([\eta] = \pu{Pa·s})$ of the gas mixture components would you recommend during adsorption at a low temperature, approx. $\pu{293 K}$ to $\pu{333 ...
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Solubility Product, and it's relation to solubility
In order to remove temporary hardness of water, it is boiled.
On boiling, while Ca(HCO3)2 gives CaCo3(ppt.) , Mg(HCO3)2 gives Mg(OH)2(ppt.).
According to my book precipitation of Mg(OH)2 occurs due to ...
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What are some Qualitative test/s that you can use for benzophenone? [duplicate]
I have determined one of my unknowns to be benzophenone and in a lab setting (but that isn't possible because of COVID-19) I would conducted the 2,4 DNP test which should yield a positive result. ...
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Method of separating product and conserving the catalyst
I'm looking for a way to separate reaction product of iodobenzene with ethyl 2-methyl-3-oxopentanoate in 1,4-dioxane (toluene is an alternative as a solvent). The catalyst being used is $\ce{Pd2(DBA)3}...
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coffee concentrate and water separated after 2 hours. How/why?
I'm asking because this makes no sense to me and making sure I'm not stupid.
I brewed 10 gallons of cold brew concentrate(TDS 12.2) and mixed it with 10 gallons of water.
I moved 10 gallons of the ...
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Reasoning about a separation problem [closed]
Describe exactly how you would go about separating a mixture of the three water-insoluble liquids, aniline (b.p. 184 °C), n-butylbenzene (b.p. 183 °C) and n-valeric acid (b.p. 187 °C), recovering each ...
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How would you separate sodium chloride and copper sulfate?
I've tried dissolving both compounds in water and evaporating the mixture, but this leaves a combination of brown and green crystals. Is there was any way to cleanly separate both compounds? Any ...
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Separating 2 chemicals [closed]
Is it possible to separate two chemicals with slightly different melting points? Can this be done with the use of a lab freezer? As MP is -44 and The other is -61 - -59 °C.
Will it solidify these ...
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How to make clean water from urine in a wastewater treatment plant? [closed]
Referring to a video here, describing a filter that treats wastewater, wouldn't urine in the wastewater not get filtered out because a sand filter alone does not separate urine from water? How is ...
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How to separate manganese(IV) oxide and chromium(III) hydroxide?
I am trying to find a reagent that keeps either $\ce{MnO2}$ or $\ce{Cr(OH)3}$ solid and make other soluble so I can centrifuge or use filtration. I thought of $\ce{NaOH},$ but I could not find any ...
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Chromatography- why tM is separated from other peaks? [closed]
tM in Chromatography is the time of exist mobile phase. But, the mobile phase exist together with all the compunds that tasted in the process. So, why in the graph of signal to time we can see a peak ...
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What is the physical property used in choosing the separation techniques for CaCO3 and KCl and NH4Cl [closed]
I've been scrolling through a chemistry past question but when I came across this I tried to solve it but it keeps confusing me
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Titration/ Separating Soluble Salts/ NaHSO4
When performing titration between NaOH and H2SO4, both Na2SO4 and NaHSO4 are formed (both are soluble in water), is there any method to obtain crystals of NaHSO4? (Maybe by separating two soluble ...
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How do we separate H2O from CO2? [closed]
Let's say I have a mixture of $\ce{CO2}$ and $\ce{H2O}$ gases. I've read that $\ce{CO2}$ is heavier (molar mass is $\pu{44.01 g/mol}$) than $\ce{H2O}$ (molar mass is $\pu{18.02 g/mol}$). So, if the ...
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Reaction between HCl and NaHCO3 [duplicate]
I want to know why in the reaction between HCl and NaHCO3, we have CO2 and H2O instead of H2CO3 ?
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How would I separate a solution of sodium iodide and water in order to obtain the sodium [closed]
I am an amateur in this field of science and I am trying to separate a solution of Sodium Iodide and water. How would I separate the solution so I can obtain sodium?
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Separation methods [closed]
I put some iron nails in water, and obviously, those started oxidizing, making those hydrogen bubbles. Some days after, the water was orange, indicated that the FeO has just dissolved in it. I found ...
