Questions tagged [separation-techniques]
For questions about the separation of mixtures and solutions into pure compounds
87
questions
1
vote
1
answer
333
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 ...
- 25.6k
7
votes
0
answers
192
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 ...
- 37.2k
1
vote
2
answers
981
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, ...
- 693
3
votes
1
answer
640
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
$\ce{HgCl2}$ ...
- 38.6k
4
votes
0
answers
386
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 ...
- 71
0
votes
0
answers
155
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. ...
- 71
3
votes
1
answer
6k
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 ...
- 37.3k
2
votes
1
answer
84
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 $\ce{^{14}C}$ ...
- 21.5k
-1
votes
1
answer
619
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
CommunityBot
- 1
0
votes
1
answer
362
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 ...
- 15.4k
-3
votes
2
answers
348
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?
- 48.4k
10
votes
1
answer
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 ...
- 43.5k
2
votes
1
answer
6k
views
How to separate sodium carbonate from sodium hydroxide?
I got a drain cleaner in dust form, which consists of $\ce{Na2CO3}$ and $\ce{NaOH}$. I wanted to extract the $\ce{NaOH}$ so I tried to heat the mixture in order to just melt the sodium hydroxide, but ...
-1
votes
1
answer
1k
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 ...
- 35.9k
3
votes
1
answer
223
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 ...
CommunityBot
- 1
2
votes
1
answer
66
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)?
- 37.3k
1
vote
2
answers
105
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 ...
CommunityBot
- 1
4
votes
1
answer
160
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 ...
- 6,444
0
votes
0
answers
44
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 ...
1
vote
0
answers
95
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. ...
- 888
2
votes
1
answer
4k
views
Separating glucose and fructose
If I have a mixture of glucose and fructose in aqueous solution, what is the simplest method to separate them? Heating to 110 °C to melt only the fructose would probably work theoretically, but this ...
- 37.2k
12
votes
5
answers
38k
views
Is it possible to separate/remove sugar from common drinks, such as juice?
Is it possible to remove sugar from a drink (for example, juice) using common household equipment?
- 6,444
2
votes
0
answers
84
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 ...
CommunityBot
- 1
4
votes
1
answer
151
views
Using cryptands to make a negatively-charged solution?
In our discussion group, my friend mentioned that metal cations can be separated from other cations in solution using cryptands. After addition of the cryptands to the solution of the cations, ...
- 37.2k
1
vote
2
answers
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.
- 37.2k
-1
votes
1
answer
166
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 ...
- 6,819
2
votes
1
answer
178
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 ...
CommunityBot
- 1
-2
votes
1
answer
839
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 ?
- 467
1
vote
2
answers
953
views
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 ...
CommunityBot
- 1
4
votes
1
answer
195
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 ...
- 12.2k
-1
votes
1
answer
67
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 ...
- 27.4k
3
votes
1
answer
74
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 ...
CommunityBot
- 1
2
votes
0
answers
48
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 ...
- 141
1
vote
3
answers
2k
views
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 ...
- 9,607
-1
votes
1
answer
3k
views
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 ...
- 9,607
1
vote
0
answers
57
views
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 ...
- 7,367
4
votes
1
answer
216
views
etymology of supernatant
Why do we call a solution that has been centrifuged a supernatant? It seems to me that a "natant" should be something that floats (from Latin "natare" meaning "to swim"), and a "supernatant" should be ...
