Questions tagged [precipitation]
For questions related to the chemical reactions and processes that result in a chemical reaching its solid phase.
210 questions
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Is there any difference between a double salt and a mixture of two salts?
Is there any difference between a double salt and a mixture of two salts? If I were to take a aqueous mixture of two salts, say NaCl and KCl, and evaporate to dryness, how is it different from a ...
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Precipitation of lead and zinc hydroxide [closed]
Excess of hydroxide forms complex with lead and zinc salts. If we add drop wise lead nitrate to a solution of sodium hydroxide the precipitates formed gets dissolved in excess of hydroxide. There will ...
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Why doesnt Grignard reagent precipitate in ether?
I read that Grignard reagents are stabilised in ether by the coordinate bond formation, but according to the Schlenk equilibrium, RMgX is in equilibrium with MgX2 and R2Mg. Here MgX2 is ionic and thus ...
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Sodium zincate reaction
does adding zinc chloride into the solution of sodium zincate formed by the reaction of zinc chloride and excess of sodium hydroxide form the precipitate of zinc hydroxide ? I mean does sodium zincate ...
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I generate a waste machine coolant that contains a chelated Cd after use. Is there anything I can add to the coolant to prevent chelation of the Cd?
I have a machining process that uses a coolant. The coolant, which contains 8-12% triethanolamine, comes in contact with a low melting point alloy during use that contains Cd and Pb. When the coolant ...
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How to extract Copper from softgel?
I have an assignment. I need to determine the concentration of copper in a pharmaceutical product using UV-Vis spectroscopy. The product is Chophyll of Healthy America, a softgel that contains: copper ...
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Effect of particle size on yield of copper acetylide
To avoid pure trial and error, I need some examples of experiments already done with (possibly ammoniacal) aqueous solutions, particles/precipitates of copper (both oxidation states) salts, and ...
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Can we replace surface stabilizers of CuS nanoparticles with a solid matrix?
Is there a method to simultaneously remove surface stabilizer molecules from $\ce{CuS}$ (copper monosulfide) nanoparticles and form inclusions of the nanoparticles into a solid crystal growing from a ...
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What precipitate forms when adding aqueous sodium sulfate solution to an unknown white solid?
I don't understand why there aren't two solutions to the following problem:
You are presented with a white solid and told that due to careless labeling it is not clear if the substance is barium ...
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How to determine the dynamic of progression of two simultaneous precipitation (double replacement) reactions? [duplicate]
We have a solution of mineral water with potassium chromate added to it, and want to titrate the chloride ions in the mineral water. We were told to use silver nitrate for this, which would produce ...
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How do you calculate the pH range for which one metal precipitates but the other stays in solution?
The problem I have been asked to solve is:
$\ce{Cd^2+}$ and $\ce{Fe^2+}$ (starting concentration $\pu{E-3 mol/L}$) should be separated by precipitation using $\ce{H2S}$. Does a pH range exist ...
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Help with Calcium Alginate Precipitation
I am a high school student working on a research project that involves producing alginate gel directly from wet seaweed. I am starting the first phase next week, which is using a small batch to ...
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Determining whether precipitation will occur or not and finding the concentration of a specific ion in a solution
The Ksp value of AY2 = 9.148 x 10^-2. I am having problem with calculating the concentration of ions. And without the correct concentration I can't find the Qsp/Kip so I'm stuck without them I can't ...
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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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Elegant and fast way without chromatography to remove fluoride ions from water phase without contamination of the polar water soluble product?
I have a challenging purification routine. I want to remove fluoride from an aqueous solution, my product is a phosphonic acid, which is readly water soluble and an anion.
The anion is about 200 Da in ...
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Decomposition of Al2S3 in water [closed]
Al2S3(s) + 6H2O(l) → 2Al(OH)3(s) + 3H2S(g)
I found this reaction on the web.I am not able to understand why this reaction proceeds from a weaker acid(H2O) to a stronger acid(H2S);contradictory to the ...
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DIY Turbidity Standards?
I am trying to help my high school chemistry class make their own turbidity standards to calibrate the arduino turbidimeters they are making. Last year we tried calcium carbonate as it makes a cloudy ...
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Mixing Boric Acid, Sodium Borate and alcohol
This is for a liquid detergent that I am developing - when I dissolve boric acid (doesn't fully dissolve though) and then mix it with dissolved sodium borate( also doesn't fully dissolve in water), ...
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Insoluble ammonium salts?
Most solubility rules I can find state that "most ammonium salts are highly soluble". I wonder if there are actually any insoluble salts containing the ammonium ion. An answer here states ...
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What is the precipitation reaction?
I asked my teacher if the reaction
$$\ce{(NH4)2CO3 (aq) + MgBr2 (aq) <=> MgCO3 (s) + 2(NH4)Br (aq)}$$
can be considered a displacement reaction. She answered that it was a precipitation reaction ...
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Would a container made of sugar eventually dissolve if filled with a sugar-saturated solution of water?
Suppose you had a bottle made of sugar glass, and filled it with water that was already saturated with sugar.
I know that with a fully saturated solution of sugar in water, no additional sugar can ...
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Why is it recommended to not store commercial sodium silicate solutions in direct sunlight, what are the effects of doing so and can it be modelled?
I regularly purchase aqueous sodium silicate solutions from commercial providers for my studies and note that a storage recommendation for all different grades (i.e. differing $\ce{SiO2 / Na2O}$ ...
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Why are iodine precipitates yellow? [closed]
Why do iodine precipitates appear yellow? Learning about precipitates I noticed that compounds like Lead Iodide and Silver Iodide are yellow.
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Is hard tap water useful for "salting out" a liquid organic solute?
We use methylene iodide ("MI", CH2I2) as a heavy liquid for sink-swim mineral separation. We use acetone to wash the MI off of the minerals and glassware after we're done. MI is pretty ...
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How do I find the minimum amount needed for precipitation?
I want to calculate the minimum amount of solid barium nitrate (g) needed to be added to $\pu{50mL \text{of} 0.05mol/L}$ sodium hydroxide in order to cause precipitation.
My attempt:
$$\ce{2NaOH(aq) + ...
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Why does CaSO4 break up when adding HCl but not BaSO4?
I observed in a solution with CaSO4 that the white precipitate dissolved when I added concentrated hydro chloric acid (37%). I assume CaSO4 had a divorce and Ca decided to hook up with two Cl- ions, ...
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Magnesium vs calcium vs barium ions from these 3 tests
How do I pick up the difference between barium, calcium, and magnesium ions? I had to do a quantitative analysis practical exam: I was given an aqueous solution of a salt, and when adding separately ...
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How to determine the amount of precipitate of a salt and product of a reaction between two solutions?
I am attempting to determine whether there is going to be the formation of a $\ce{AgCl}$ salt precipitate if the following two solutions were to be added together:
$50mL$ of $\ce{NaCl}$, $0.04M$,
$...
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Why and how do aqueous silica systems precipitate and can its occurrence be mitigated by quantifying its speciation correctly?
Background/Context:
For context, I have been doing a lot of work on experimental systems in geopolymer chemistry lately with a focus on "activator" solutions which are essentially mixtures ...
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How does temperature affect ionic Ca in milk
I’m doing an investigation on the effects of temperature on ionic calcium content in milk through a classic EDTA titration method and have a few questions:
— what is the scientific theory behind the ...
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Will ethanol precipitate lipid-saccharide compounds?
I have a cell-free solution of culture broth. It contains a wide range of compounds ranging from salts (marine broth), lipids, and proteins to polysaccharides.
My goal is to extract all type of ...
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Does nickel precipetate gold and copper?
I dissolved some CPU s and RAM s in aqua regia the day after I found a green solution with black powder in the bottom. So what just happened is it nickel or tin from solder?
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How to theoretically determine if a hydrate of a salt precipitates out of solution
In a solid-liquid extraction simulation process, there are multiple salts that precipitate in the solution. But how do I determine if these salts are hydrates or not? To give an example:
$$\ce{Ca3(PO4)...
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Why urea crystallizes in aqua regia? [closed]
Recently I stripped gold from old cpu's with ferrous chloride after that I rinsed the cpu's and dissolved them in the aqua regia to get the gold inside when all done, I added urea solution to the ...
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Isolating potassium chloride from sodium chloride and potassium hydroxide
Assume that you have an aqueous solution of sodium chloride and potassium hydroxide. Is it possible to isolate potassium chloride from this?
$$\ce{Na+(aq) + Cl-(aq) + K+(aq) + OH-(aq) -> Na+(aq) + ...
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What happens when we react a sulfate salt solution with barium chloride and the formed precipitate with conc. hydrochloric acid?
When I performed this experiment in my school, I could not observe any sort of remarkable change (I must have performed it incorrectly or something).
I wanted to know what should have been the correct ...
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How do I separate an Indium-Gallium alloy into Indium and Gallium?
I've recently learned more about Indium and Gallium, and I find them quite interesting, especially how an alloy can be manually made simply by rubbing them together. I'm curious though, is there a ...
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Precipitation of equimolar amounts of chloride and bromide [duplicate]
I was just wondering about the following situation; if we had a solution containing 0.1M bromide and 0.1M chloride ions, and treated it with excess silver nitrate, what would happen and would ...
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Converting dissolved chromates to solids for disposal
I have 4 liters of electrolysis waste that was used to process stainless steel cathodes.
About half of it was oxalic acid based and the other half was sodium bicarbonate based (currently stored ...
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Does Sodium Precipitate with anything to find the level when titrating?
I am trying to find sodium in animal feeds. I already have a procedure to find chloride by using Mercuric Nitrate to form Mercuric Chloride using a titration method but am having a difficult time ...
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How to determine whether a solid has dissolved or no reaction occurred? [closed]
From this link: https://chemhaven.org/che111/lab/Lab_9_Unknown_Anion_F21.pdf
When dissolving a solid or precipitate,
only a portion is dissolved, thus leaving some behind, and fooling a student into ...
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Are there any cold temperature reactions in liquid where ice forms as a precipitate?
The title asks the entire question, but I'll elaborate:
Precipitates form in aqueous reactions when some product is insoluble in water. Is there a reaction in some other solvent where solid water ...
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The meaning of USFDA (in cosmetics) [closed]
The full meaning of USFDA base on the definition of cosmetic meaning and production
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Is BaSO4 (barium sulphate) soluble or insoluble in diluted HNO3 (nitric acid) and diluted HCl (hydrochloric acid)? [closed]
Here's the original question , I was asked in an exam :
Edit : the question in the picture is a single correct multiple choice question
I have concluded the the reaction of Barium chloride and Sodium ...
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Displacement of salts due to higher solubility
I was wondering why mixtures of salts in the same solution precipitate excactly in order of their solubilities. Imagine a solution with NaCl, NaBr, NaI in equal moles. If AgNO₃ solution is now added ...
user115162
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How to predict colour of precipitate? [duplicate]
I am currently preparing for Junior science competitions and I am coming across many questions where colour of precipitate plays important role... Like
When compound $\ce{Hg2(NO3)2}$ reacts with $\ce{...
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Why use "molecular equation" to refer to a chemical equation describing a precipitation reaction?
When we describe a precipitation reaction using a chemical equation, we have the choice of either writing the net ionic equation (i.e. leaving out spectator ions) or writing the respective ionic ...
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Why does the reaction between copper(II) ion and iodide ion proceed even though the E_cell of the set up is negative?
(iii) Another example of a reaction that does not agree with the theoretical prediction is the reaction between $\mathrm{Cu}^{2+}$ and $\mathrm{I}^{-}$ according to the equation below.
$$
2 \mathrm{Cu}...
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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 ...
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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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