Questions tagged [separation-techniques]
For questions about the separation of mixtures and solutions into pure compounds
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Why are cations detected in capillary gel electrophoresis with a positive applied voltage and a coated fused silica capillary?
In capillary gel electrophoresis, when a positive voltage is applied to a coated fused silica capillary, why are positively charged ions (among positive, negative and neutral) detected first?
What is ...
3
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1answer
74 views
How are Silanol groups functionalized unto mesoporous silica structures?
As described in this research paper:
Immobilization of Jacobsen type catalysts on modified silica, Jairo Cubillos , Edwing Grajales, Santiago Vásquez, Consuelo Montes de Correa, Rev. Fac. Ing. Univ. ...
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61 views
How do I get calcium citrate to precipitate in experiment on extraction of citric acid from juice?
I was planning to extract citric acid from mango juice by first using Aspergillus niger fungus by fermentation to convert the mango juice to citric acid, then extracting by first adding sodium ...
7
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2answers
800 views
How to separate Cu and Ni from alloy containing different metals such as Al, Cu, Ni, (Zn, Pb, Sn < 5%)?
I have an alloy containing different metals such as Al, Cu, Ni, (Zn, Pb, Sn, Ag, Si in small amount < 5%). How can I separate Cu and Ni from this alloy?
I tried to dissolve alloy in sulfuric acid, ...
0
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1answer
272 views
Which process would separate the mixture of toluene, cyclohexane and water?
toluene: $\ce{C6H5-CH3}$
cyclohexane: $\ce{C6H12}$
I think that answer would be:
Toluene and cyclohexane do not dissolve in water (since they are nonpolar), so I would first separate the water from ...
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1answer
41 views
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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46 views
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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29 views
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 ...
0
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2answers
684 views
how to separate a mixture of sodium chloride and sodium hydroxide
I recently did an double displacement reaction in that I have formed a solution of water with sodium hydroxide and sodium chloride are dissolved in it. now I want to separate both of them
1
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2answers
368 views
How to make acetic acid more volatile so that it can be removed by vigorous aeration of an acetic acid-water mixture? [closed]
I want to remove acetic acid from a mixture of acetic acid and water by aeration. The concentration of acetic acid is 200 ppm (mg/L). The pH of the water is more than 5. I want to reduce the acetic ...
2
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0answers
283 views
Purification of Red Phosphorus
The Boring Stuff
I'm well acquainted with various fields of science & engineering, but my foray into the world of chemistry is relatively recent.
I'm in a location (probably most of us are to some ...
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29 views
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 ...
2
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2answers
158 views
Ways to determine the concentration of alkyl halides in organic solvents
I have a volatile alkenyl bromide dissolved in hexanes. I have to use the halide in a Grignard reaction but separating it from hexanes is hard (the bromide is light sensitive and very volatile). I ...
1
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1answer
96 views
Separating sodium sulfate from chromium trioxide solution
I was looking at the industrial process for the production of chromium trioxide by treating sodium chromate or the corresponding sodium dichromate with sulfuric acid. This results in the formation of ...
3
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1answer
109 views
How do you separate microcrystalline cellulose from amino acids in a powder mixture?
I am looking to separate out the microcrystalline cellulose that has been mixed in with amino acids in a powder mixture.
I have tried suspending the powder mixture in water and then filtering out the ...
4
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2answers
164 views
How much does oxygen enrichment improve some combustion engines?
This question is about how much the combustion efficiency increases with oxygen enrichment in modern combustion engine designs. A desirable way to answer is to give the fuel efficiency dependency on ...
1
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1answer
194 views
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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0answers
143 views
Distilling milligram quantities of oil like it's late 1970s
In a currently retracted* manuscript by Tomas Hudlicky [1, Retraction Watch] the following has been noted:
Fifty years ago professors took an active part in all laboratory instructions and they ...
2
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1answer
340 views
Why does HgCl2 react with HCO3^- but not with CO3^2-?
I have started learning Qualitative Salt analysis recently. When I was reading about tests to distinguish $\ce{CO3^2-}$ and $\ce{HCO3-}$, I came across a line in a book which states
$\ce{HgCl2}$ ...
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119 views
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. ...
4
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0answers
185 views
How can should one separate and purify benzophenone from salicylic acid?
I am working with two solids and I know that they are benzophenone (s)(ketone) and salicylic acid (s) (carboxylic acid). I am curious to know what is/are the best method of extraction and ...
1
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1answer
102 views
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 ...
3
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1answer
4k views
Separating lanthanides using ion-exchange method
Following statements are on Separation of rare earth metals (lanthanides) via in-exchange method
The tripositive ions are strongly sorbed by cation exchange resin: $\ce{La^{3+}}$, the largest is ...
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2answers
444 views
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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1answer
230 views
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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1answer
259 views
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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2answers
170 views
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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50 views
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}...
10
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1answer
3k views
What is the scientific term to describe the operation of a bong?
What is the scientific term for the separation of dust particles from air by suction through a specialized flask in a way similar to the operation of a bong?
The thing that led me to this was a ...
2
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1answer
69 views
Does the distillation of alcohol cause the fractioning of isotopes and carbon-12 enrichment?
In water, distillation causes fractioning of the $\ce{^{18}O}/\ce{^{16}O}$ oxygen isotopes (Wikipedia).
Does something similar happen to the $\ce{^{13}C}/\ce{^{12}C}$ and possibly $\ce{^{14}C}$ ...
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1answer
763 views
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 ...
3
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1answer
116 views
Do companies recover carbon dioxide and water from the purification step of cryogenic air separation, and how?
In the 3rd step of cryogenic air separation, filtered air is purified to remove water, $\ce{CO2},$ and hydrocarbons from the $\ce{N2}$-$\ce{O2}$-$\ce{Ar}$ stream. Im interested in knowing what happens ...
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1answer
118 views
Separation of methanol–water mix in a plate distillation column
I conducted an experiment to separate methanol and water. I am trying to determine the mole fraction of the distillate collected but having a little trouble with the calculation.
The flow rate was $\...
2
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1answer
50 views
HPLC Columns For Compounds Not Soluble In Non- Or Low Polar Solvents [closed]
Can someone recommend HPLC columns for compounds which are not soluble in no- or low polar solvents (hexane, isopropanol, toluene, and dichloromethane)?
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33 views
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 ...
3
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1answer
141 views
How to conveniently separate Cd impurities from ZnO without contaminating it?
How could I separate Cd impurities from ZnO without contaminating it and without using overly expensive equipment or extremely dangerous solvents?
I don't want to contaminate it by introducing other ...
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0answers
67 views
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. ...
2
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1answer
4k views
How to remove sugar from juice
My son has autism and we noticed that blueberries make him feel much better. The problem is blueberries contain sugars which interfere with diet he has (low carbohydrate).
How do I filter out the ...
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2answers
84 views
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 ...
2
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0answers
65 views
Is there a way to form only ortho product without using fractional distillation?
Using benzene and ethane as your only source of carbon in the final molecule, synthesize the following using any useful reagents. Reaction must form pure ortho compound.
I have to form the product ...
3
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2answers
678 views
What is the principle of “scrubbing” in liquid extraction or solvent extraction?
There are many steps in solvent extraction:
Extraction
Scrubbing
Back extraction
I understand the 1st and the 3rd.
What is the principle of scrubbing?
Is it just washing the organic phase?
How ...
4
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2answers
679 views
Shea Stearin Extraction by Dry Fractionation
I have been able fractionate palm oil and extract palm stearin using the following method:
Melt the palm oil (over 80 °C)
Keep the melted oil at 33.5 °C for 24 hours (using an immersion circulated ...
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1answer
117 views
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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1answer
705 views
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 ?
4
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1answer
171 views
Recover Solder (Sn-Pb) from wires
I have began to do an "art project" which utilizes solder as main material.
While I know that solder is cheap and easily found in multiple shops, I have set my mind on using recycled solder from out ...
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2answers
2k views
How to separate two liquids with both having the same properties?
I was curious if it was possible to separate such liquids e.g. two vegetable oils that happened to have different ingredients, so it is a different liquid, but the same density etc.
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1answer
58 views
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 ...
2
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1answer
138 views
Separating specific components of a PUREX raffinate
The PUREX extraction in nuclear fuel reprocessing leaves behind a nitric acid raffinate full of (mainly) 'fission products', which are a diverse set of elements produced by fission in a nuclear ...
3
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1answer
67 views
Is the pressure in an HPLC system the same throughout?
I'm not sure if I'm articulating myself well enough, but here's my problem: I have a current HPLC system, where we typically have backpressure readouts of around 15 MPa. We are looking to get a new ...
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0answers
41 views
Hypothetically, can sufficiently powerful centrifugation separate normally miscible chemicals of differing densities?
Centrifugation is used to separate phases in suspensions by density. I read that this is not possible with colloids and solutions, but the distinction between the three seems to be optical properties ...
