Questions tagged [identification]
Questions asking for identification of compounds in photos, by description, or given by a formula.
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Mysterious violet-purple compound in "Gerber Method" & "Banana oil synthesis"
During the determination of fat in milk (Gerber method), in a milk butyrometer are mixed milk + $\ce{H2SO4}$ 90% w/w + isoamyl alcohol (isopentyl alcohol) and heating.
The acidic mixture separates ...
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What material is used in coating these aluminum containers for the food industry?
What is the material used to coat (some might use the term 'lacquer') disposable aluminum containers in the food industry? And can it be removed in a safe way (for the environment) with 'home methods'?...
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Determine if particles are aluminium oxide
I am getting a white dust in my car, coming from the air vents and landing all over, mostly on the dashboard. After searching about this, it seems that it could be caused by the fins of the air ...
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Explanation of colours of solder plated copper pads after electrolysing a circuit board in NaCl solution
A last ditch method for identifying connections in a old multilayer circuit board that I have come up with, when you have a spare, is to put the board in salt (NaCl) solution and connect a power ...
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What compound was drawn on this sidewalk?
A friend found this in the sidewalk of Kent town of Canterbury:
What compound is this, and why would its picture be there?
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Could you tell me the name of this compound please? [closed]
Could you please tell me make of this compound?
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Can I use potassium ferricyanide instead of potassium ferrocyanide for the identification of calcium?
I have to perform the identification test of calcium ion in calcium gluconate. I do not have potassium ferrocyanide for the test but I do have potassium ferricyanide. Can I take the ferrocyanide form ?...
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How can I test for impurities in my steel wool?
I am trying to purify ferrous sulfate (for some electroplating experiments) and I came up with the following process:
Dissolve 200g of iron fertilizer in 300ml of distilled water heated to 54 °C (...
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Is it always necessary to boil off H2S(g) to test for group III cations in qualitative analysis?
When a sample contains $\ce{Al^3+}$ ions (group-III), to test for its presence, before adding NH4Cl/NH3 solution do we need to boil off acidic H2S added earlier to check for the presence of group-ii ...
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How are substances identified in the real world? [closed]
Recently in AP Chem I did a lab that involved doing various tests (melting on hot plate, flame test, etc.) to identify a metal out of a list of metals.
This had me wondering: how do chemists identify ...
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How to identify unknown, insoluble solid with limited resources?
Looking for suggestions on how to identify an unknown white solid we received as a donation. It was originally labeled as $\text{MgSO}_4$, but clearly is not. We suspect it might be $\text{CaSO}_4$. ...
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What compounds smell like burning rubber or tar?
Background:
A couple of friends of mine live next door to each other in a 10-year old block of flats in London, UK. They say that in the early hours of the morning, a toxic smell appears in their ...
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Formula of what substance is shown in the clip Disappointed by Electronic? [closed]
I'd like to know the substance (if any) the model of which is shown in the clip Disappointed by Electronic.
The following screenshot is taken from the video electronicofficial —
Electronic - ...
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Could mixing naphtha-based cleaner and industrial floor cleaner produce hazardous substances?
I work in a car dealership, and the guy who cleans the workshop uses an industrial floor scrubber / vac on the floor tiles. On particularly stubborn oil / soot marks, he uses naphtha-based brake ...
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Hypothetical symmetric carbon peroxide
Could a hypothetical carbon peroxide $\ce{C5O12}$ with the following structure (MolView — 3D model) exist, and I what its properties would be (other than decomposing, of course)?
I tried looking it ...
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What organic molecule, if any, does this diagram represent in Louis CK's "Louie" Season Four, Episode Eleven, just before the six minute mark?
I'm wondering what molecule this is, if any, and whether this molecule is even physically likely or possible.
Here is a screenshot of the scene from "Louie" (a hilarious and fascinating ...
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Is this plastic clip made of polypropylene or polyethylene?
I am trying to re-attach an automotive clip (painted plastic with a yellow (epoxy?) hard adhesive backing) which secures a trim piece back onto the vehicle's roof sheet metal (unpainted (primed?) area)...
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What molecule is pictured on the cover of Dead Sara's album "Ain't It Tragic?"
An album released today by Dead Sara, titled Ain't It Tragic, has a chemical structure on the album cover. Here's a close-up of that structure:
As the structure is partially obscured, it's difficult ...
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What molecule is this. Pretty sure its not ethanol? [closed]
This is the molecule in question
This in advance.
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Does the largest known cycloalkane contain 288 carbon atoms?
If you Google "largest known cycloalkane", you will find this:
The above result came from a random HW-QnA site. From where does the result come from?
Similar posts:
Largest alkane having a ...
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What reaction happens between glucose and ammonium chloride when drying?
I have the following observations:
When I put a solution of glucose (80 g/ℓ) and ammonium chloride (20 g/ℓ) in a drying cabinet at 37°C (maybe a bit warmer) a brown substance forms when all (or most) ...
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Ambiguity in the direction of dissolution equilibrium
The following reaction is usually carried out to test for the carbonate anion in an inorganic salt;
$$\ce{CO3^2- +BaCl2/CaCl2 -> BaCO3/CaCO3(s) + 2 Cl-}$$
The resulting carbonate is stated to be an ...
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Detection of sulphide in solution also containing sulphate
Question:
The reagent(s) that can selectively precipitate $\ce{S^2-}$ from a mixture of $\ce{S^2-}$ and $\ce{SO4^2-}$ in aqueous solution is(are):
(A) $\ce{CuCl2}$
(B) $\ce{BaCl2}$
(C) $\ce{Pb(...
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Can we use silver nitrate to distinguish between chloride and carbonate salts?
Initially, we are given a solution containing two salts, they can be either carbonate or chloride salts (we do not know their composition initially).
Generally, $\ce{AgNO3}$ is used as a confirmatory ...
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Meaning of "Nonyl-phenol 10 mole"
In my workplace we are purchasing "Nonylphenol 10 mole" and "Nonylphenol 30 mole" for use as non-ionic surfactants.
At first I assumed, because of the name, that the substance was ...
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Are atom coordinates in molfile necessary to produce a valid InChI identifier
I took this molfile of benzoic acid:
...
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How to identify the aromatic compound with the sum formula C7H6Cl2?
An aromatic compound (A), $\ce{C7H6Cl2}$, gives $\ce{AgCl}$ on boiling with alcoholic $\ce{AgNO3}$ solution and yields $\ce{C7H7OCl}$ on treatment with $\ce{NaOH}$. (A) on oxidation gives a mono-...
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Why do we need weak or strong acids to displace the anions of other weak acids from salts?
I have already looked at Why does a strong acid displace salt of weak acid? but I couldn't understand the answer and the analogy there. And I mean the above question in the following context :
$\ce{...
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What would be the identification reactions of selenate(IV) ion? [closed]
I have not been able to find any $\ce{SeO3^2-}$ identification reactions anywhere. Are there any?
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What's the usual agent added to discourage drinking of hazardous substances
I've once read somewhere that in materials that are hazardous to swallow, a chemical is used in very small quantities to assure any accidental drinker to retch. This also helps to prevent suicide by ...
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Identification of aqueous solutions of sodium hydroxide, sodium acetate and potassium thiocyanate using nickel(II)
I'm very new to chem — taking an intro to chemistry course where we are currently focused on substance identification. I have two substances, both aqueous solutions of either $\ce{NaOH},$ $\ce{KSCN},$ ...
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Name of this bond-line formula? [closed]
I don’t know much about chemistry but I recently found the below bond-line structural formula painted on a wall near my place. I really can’t let go of trying to find the name of the compound. If ...
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Yellowing/Browning from Mixing Ascorbic Acid with Calcium Carbonate and Glycerol
I slowly get some yellowing / browning upon mixing ascorbic acid with calcium carbonate and glycerol and letting it sit at room temperature over time.
At first I thought it was ascorbic acid oxidating ...
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What happens when an alkyne reacts with ammoniacal Cu2Cl2?
My text book provided me with 2 reactions concerning alkynes (Specifically Terminal Alkynes).
The first one was the dimerisation of an alkyne on passing it through ammoniacal $\ce{Cu2Cl2}$.
All was ...
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Is there any easy trick to know if a substance is a Brønsted–Lowry acid or base? [duplicate]
I know that Brønsted–Lowry acids can donate a proton and a Brønsted–Lowry base can receive a proton. I have also memorized the strong acids and bases, which makes it easier to figure out. However, if ...
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Identify the structure of compound with C₉H₁₀ formula using IR and NMR data [closed]
Use IR and NMR data to define the structure of the molecule, the formula of the given structure $\ce{C9H10}.$
On what basis do we conclude that its structure is that (the answer) only? On what points ...
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CAS id to SMILES
How can I convert a list of CAS ids to structures (SMILES). I have been trying (Chemspider API, PubChem and the chemical identifier Resolver) but there are still some ids I can't find the structure. ...
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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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What is "dithreitol"?
The article by Hu et al. [1] mentions a compound "dithreitol" in the Saliva Proteome Analysis section (emphasis mine):
For the "shotgun" approach, saliva samples (1 mL) were pre-fractionated with ...
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How can chemists distinguish pure chemical element specimens that look almost "the same" as well as what deposit is what in a multimineral mined rock?
As a non chemist I am most often charmed when visiting Wikipedia articles of chemical elements and see images of very pure specimens of element after element, proton by proton, and often also metal ...
user61828
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Can 2‐chloropropane and acetyl chloride give the iodoform test?
Can $\ce{CH3-CHCl-CH3}$ and $\ce{CH3COCl}$ give the iodoform test?
I thought $\ce{CH3COCl}$ having the keto-methyl group would show the iodoform test, while $\ce{CH3-CHCl-CH3}$ will not since it's ...
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Which compound should I avoid in deodorants to avoid "sticky, unwashable" feeling?
I tried some personal deodorants to avoid the smell of sweat, both in stick, no gas, gas sprays. Some can be washed away easily with body soap on the next day, some require either hair shampoo (...
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Identifying molecule with three adjacent six-membered rings from blurry image
I have found this isolated image on one of my old hard drives and I would like to know what molecule does the image represent:
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What is this fluorinated organic substance?
The corresponding author of the paper where this formula was published as appendix passed away. Can someone help me with identifying what is the name of this compound and why have strange zig-zag ...
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Flame test color for non-ionic compounds
What color would a non-ionic compound, such as $\ce{NH4OH}$ or $\ce{HCl}$, produce in a flame test? Is no color produced, or is it different for each compound?
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Removing sodium borate for the test proving thiocyanate ions
I've just learned that when carrying out the identification test for thiocyanate ions borax can induce a false positive and therefore needs to be removed. I couldn't find the answer on google so I'm ...
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How do I identify the compound(s) that formed from a failed synthesis of another compound?
A general answer to the question is great, but specified to my problem is very much welcomed.
My team had a lab project — to synthesize chrome alum crystals.
We first dissolved $0.3 \, \rm g$ of ...
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What gas was produced in this orbiting space-balloon from 33 pounds of benzoic acid and anthraquinone? Why these two chemicals?
As pointed out in this answer, on page 4 of NASA Technical Note TND-1366 The Orbital Behavior of the Echo I Satellite and its Rocket Casing During the First 500 Days (June, 1962) says:
PHYSICAL ...
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Is there another name for compound "delta-7 sterine", does it exist alone?
Is there a more common name for "delta-7 sterine"? Is this spelled correct?
I read all over the internet and this compound exists in many articles, but I cannot find any information on it at all, ...
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What are methods of identifying which amino acids are in a sample of protein? [closed]
Are there any methods out there to identify which amino acids are in a sample of protein? Perhaps using NMR?
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