Questions tagged [precipitation]
For questions related to the chemical reactions and processes that result in a chemical reaching its solid phase.
147
questions
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Free Energy vs. Common Ion Effect in Ultrapurification
I'm wondering which of the two phenomenae grows in importance and which one becomes irrelevant when the proportion of impurities in a product being purified become increasingly small:
The common ion ...
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0answers
38 views
What is this brown coating in my desert cooler? [closed]
I saw this brown coating on the top side of my desert cooler.
From the top left side water is pumped up and it leaves from the many holes on the bottom of the image and wets the grass which cools the ...
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0answers
8 views
Material properties differing between vacuum or pressure filtration
During vacuum filtration of a very fine suspension, all solids that need to be removed are, but there is minimal solids loss. If the same material is pressure filtered (1-2 bar), desired solids ...
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2answers
46 views
Seperating out iron from ferrous sulfate
I don't need to necessarily seperate pure iron, but from a ferrous sulfate solution, I am trying to form a precipitate with iron. By getting a precipitation of an iron compound, I can find out the ...
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4answers
83 views
How many grams of sodium phosphate must be added to precipitate as much of one ion as possible?
Problem text:
Solid sodium phosphate is slowly added to $\pu{200 mL}$ of a solution containing $\pu{0.002 mol}$ of aluminum chloride and $\pu{0.001 mol}$ of calcium chloride (assuming no volume ...
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1answer
53 views
Using solubility product to determine the mass of the precipitate of a reaction
I mix together $\pu{100 mL}$ of an aqueous $\ce{NaCl}$ solution at $\pu{0.5 M}$ and $\pu{100 mL}$ of an aqueous $\ce{AgNO3}$ solution at $\pu{0.3 M}$. Assuming that the solubility of $\ce{NaCl}$ in ...
2
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0answers
34 views
Which salts precipitate from a potassium/sodium chloride/sulfate solution?
This is not a homework question. I am not in any course of study. The following question arises from my personal curiosity. If 1 mole of sodium sulfate and 2 moles of potassium chloride are dissolved ...
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76 views
Why does silver stick to the glass in Tollens' test? [duplicate]
Why does it not simply form a solid powder at the bottom of the flask?
Does silver also stick to the glass in other silver precipitating reactions?
EDIT:
My question is definitely not the same as ...
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1answer
67 views
Qualitative Analysis- Distinguishing between two ions or two salts [duplicate]
I know my question is going to be quite below the level of this site but I am 1st grade in university and I can't understand anything.
I am going to give an example from the book: distinguish ...
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2answers
41 views
How can I dissolve a precipitate when stuck to the side of a boiling flask
Iāve been experimenting with producing Iron Acetates and Iāve run into a snag. Hereās my process so far:
I started by adding white vinegar and ~50% Hydrogen Peroxide to a reaction vessel with steel ...
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1answer
33 views
Solutions and Precipitates [closed]
If a solution of $\pu{20mL}$ of $\pu{ 0.050M}~\ce{K+ }$is added to $\pu{80mL}$ of
$\pu{0.50M}\ce{ClO4-}$ will a precipitate form and what is the value of $Q_\mathrm{sp}$? For $\ce{KClO4}, K_\mathrm{...
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26 views
Will calcium concentrations be reduced when water is boiled at lower atmospheric pressure? [closed]
It's well documented that one can reduce calcium concentrations in water by boiling the water. This is caused by CO2 being driven out of the water and the calcium precipitating out of solution. Ok, ...
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0answers
235 views
DIY hand sanitiser solution forms spongy substance
I am trying to make my own hand sanitiser since itās sold out everywhere. The formula I use is 1 part aloe vera gel in 2 parts 100% isopropyl alcohol. The problem is when mixing the two, the solution ...
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2answers
55 views
Remove carbon dioxide from solution [closed]
What solution could I add to a solution of water with dissolved carbon dioxide in order to get the carbon to precipitate out? I believe the ions are H+ and HCO3-
Thanks, Jerid
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3answers
70 views
Is the kinetic energy change of a system (q) equal to the enthalpy change of a system (āH)?
When silver nitrate and hydrochloric acid are put together in a container, they form silver chloride. If you're given information about the reactants (including temperature change, heat capacity, and ...
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1answer
82 views
How to precipitate Chloroplatinic acid? [closed]
For the precipitation reaction, I have to react $\ce{H2PtCl6}$ with $\ce{(NH4)2CO3}$ while maintaining the $\ce{pH}$ in the range of 7-8 at 60 Ā°C. But the problem is Chloroplatinic acid is not ...
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1answer
28 views
Effect of reduction potential on particle size of chemically precipitated silver particles [duplicate]
Is there no mathematical relationship between redox potential and particle size saying that an $X$ potential should yield a $Y$ particle size? Right now its general that large redox potential results ...
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1answer
31 views
Is there a name, or any specific jargon for a precipitation equilibrium involving a solid reactant?
Let's say you have some ions in solution, for example Na+(aq) and OH-(aq), and some partially dissolved solid, MgCO3(s), Mg+2(aq) and CO3-2(aq), which precipitates Mg(OH)2(s) until equilibrium.
So ...
1
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2answers
148 views
Will NaF + CaCO3 precipitate much CaF2?
If I mix sodium fluoride, calcium carbonate powder, and water, under what conditions (if any) would there be an equilibrium?
I.e. assume we start out with fully dissociated $\ce{Na+(aq) + F-(aq)}$, ...
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0answers
26 views
Ideal characterization technique to study behavior of heated metal nitrates
I have 3-4 metal nitrates as precursors for my coprecipitation reaction. I need to study the behavior of each individual nitrate and also of various combinations at 60 degrees Celsius, which is my ...
4
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3answers
133 views
Does brewing tea with hard water reduce the amount of bioavailable fluorine?
I read that brewed tea contains a relatively large concentration of Fluorine.
Fluorine can have negative health effects such as Skeletal Fluorosis. EDIT: I understand some Fluorine is necessary and ...
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2answers
60 views
Preparation of Barium Hexaaluminate using co-precipitation reaction mechanism
I am preparing Barium Hexaaluminate (BHA) using $\ce{Ba(NO3)2, Al(NO3)3}$, and $\ce{(NH4)2CO3}$. For $\pu{1 mol}$ of each $\ce{Ba(NO3)2}$ and $\ce{Al(NO3)4}$, I am using $\pu{1.5 mol}$ of $\ce{(NH4)...
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1answer
44 views
How to calculate the amount of sodium sulfate needed to lower the silver ion concentration of a saturated silver sulfate solution?
How many moles of $\ce{Na2SO4}$ we have to add into a saturated $\pu{0.5 L}$ solution of $\ce{Ag2SO4}$ so that the concentration of $\ce{Ag}$ is $\pu{4.0 \times 10^-3 M}$? ($K_\mathrm{sp} = 1.4 \times ...
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2answers
75 views
Calculating equilibrium concentrations of silver and halide ions
$\pu{500 ml}$ of $\pu{0.01 M}$ $\ce{AgNO3}$ is mixed with $\pu{500 ml}$ of solution containing $\pu{0.1 M}$ $\ce{NaCl}$ and $\pu{0.1 M}$ $\ce{NaBr}$. $K_\mathrm{sp}$ of $\ce{AgCl}$ is $10^{-10}$ and $...
4
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1answer
194 views
Is chromate a suitable indicator for the titration of Agāŗ with Clā»?
To titrate $\ce{Cl-}$ with $\ce{Ag+}$ we use chromate $\ce{CrO4^2-}$ as an indicator.
The titration reaction is:
$$\ce{Ag+ + Cl- <=> AgCl}\tag{R1}$$
$$K_1 = \frac{1}{K_\mathrm{sp}(\ce{AgCl})} =...
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0answers
19 views
Method to find out the amount of solvent replaced by another solvent
So I am performing a relatively simple coprecipitation experiment to synthesize ceramics. All my precursors are in aqueous solutions. But due to the high surface tension of water, drying the water is ...
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1answer
34 views
Selectivity of metal nitrates towards ammonium bicarbonate
I am performing coprecipitation reaction, and in the precipitating step, I have a bunch of metal nitrates(ferric nitrate, aluminium nitrate and barium nitrate)in a solution reacting with ammonium ...
1
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1answer
65 views
Precipitation of water-insoluble materials from shower or laundry greywater
I am currently working on a project to build a filter that aims to separate or salt out the 'dirt' in shower or laundry greywater. The ideal result from this chemical reaction will be such that the '...
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2answers
63 views
Predicting a precipitate based on Ksp
$\pu{105 mL}$ of $\pu{0.10 M}$ $\ce{AgNO3}$ is added to $\pu{125 mL}$ of $\pu{0.35 M}$ $\ce{K2CrO4}.$ Will a precipitate form? $(K_\mathrm{sp}$ for $\ce{Ag2CrO4}$ is $\pu{1.12E-12}.)$
Answer:
Can ...
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3answers
1k views
How do Precipitation Reactions behave in the Absence of Gravity?
How do precipitation reactions behave in the absence of gravity, say on the International Space Station (ISS)? I have seen water taking the shape of a sphere and not that of the container in space due ...
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0answers
24 views
Can classification techniques used for identifying solids be used to identify precipitates?
I am preparing for an assessed practical experiment where an unknown precipitate must be identified. I know that precipitates are insoluble, and my textbook says they are considered to be solid with ...
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1answer
29 views
Using a weak acid to prevent the precipitation of Mg(OH)2
I have this exercise in my chemistry book, and I have been staring at it for so long but unfortunately I have no single idea what to do and where to start. I will be so thankful for any help.
$0.05$ ...
4
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1answer
116 views
Why is only the carbonate anion used to precipitate Barium?
Q: Why is the $\ce{CO3^2-}$ anion used to precipitate Barium from $\ce{BaBr2}$ and not another anion, such as $\ce{PO4^3-}$, or $\ce{SO4^2-}$?
I am studying high school Chemistry, and the current ...
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1answer
500 views
Which metal ions precipitate in NH4OH? [closed]
From Wikipedia-1, and from an answer here on Stack-Exchange, I can list at least the following elements which will dissolve in aqueous $\ce{NH4OH}$:
$\ce{Cr(III), Co(III), Ni(II), Cu(I, II), Zn(II), ...
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2answers
359 views
Which salts can be used to precipitate chloride ions? [closed]
We donāt have AgNO3 in the lab. I have no idea what else can be useful.
I am washing a product and I want to make sure the chlorides are washed away.
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1answer
46 views
Can I safely use a separatory funnel to extract the precipitate from a solution?
Can a separatory funnel be used to collect a precipitate, or would that risk clogging the stopcock on it?
I'd like to recoup the precipitate for filtering without passing the entire solution through ...
0
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0answers
45 views
Why does Mg(HCOā)ā on heating gives Mg(OH)ā? [duplicate]
Normally, bicarbonates on heating forms carbonates.
Why does Mg not give this too?
In a reference book I am referring to, it is given that it is due to high solubility product of Mg(OH)ā compared to ...
2
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1answer
267 views
How to find the concentration of barium ions in a mixture of barium sulfate and barium thiosulfate?
I have a hard time with selective precipitation problem.
A mixture of $\ce{BaSO4}$ and $\ce{BaS2O3}$ is shaken with pure water until a saturated solution is formed. Both solids remain in excess. ...
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3answers
580 views
CaSO4 precipitate in mixture of Na2SO4 and CaCl2 solutions
I have been stuck on a chemistry problem for a long time now and if anyone here can help me I would be eternally grateful.
40. Du tillsƤtter $\pu{100 ml}$ $\pu{0,01 M}$ $\ce{Na2SO4}$-lƶsning i $\pu{...
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0answers
23 views
Cleaning a stubborn Electrospray residue
I have an electrospray ionization capillary tip that sprays into a chamber that contains some circuit boards. An aqueous CsI sample is apparently causing a white residue to build up on these boards ...
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1answer
125 views
Precipitation of Cu2+ and Pb2+ ions
Hi chemistry enthusiasts!
I am working on my scholarship exam practice. I believe this exam assumes high school + first year university knowledge although the standard may be varied across the world. ...
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1answer
2k views
Are precipitations exothermic and/or endothermic?
Should be an easy one. I'm fumbling a concept. I've read precipitations are exothermic. Is this accurate? Why would there be no endothermic precipitation reactions?
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1answer
91 views
Making hard water
Does anyone know how to make hard water with a hardness of 200+ ppm in terms of $\ce{CaCO3}$?
I live in Seattle and we have very soft water and we need hard water for testing purposes. Obviously you ...
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2answers
31 views
Influence of pH on precipitate crystallite sizes?
It's normally assumed that a higher pH of solution would slow nucleation rates and hence lead to larger crystal formation. I've found literature that it is due to solid-liquid inter-facial tension. ...
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0answers
499 views
Eutectic Phase Diagram of Al-Si Analysis
Hello,
How can I know from this phase diagram:
1. The composition of the alloy Al-Si that allows precipitation to occure?
2. The range of temperatures where the Al-Si is soluble?
3. The range of ...
1
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1answer
66 views
How to convert soluble colorless [HgIā]²ā» back to insoluble red HgIā? [closed]
When a solution contains $\ce{Hg^2+}$ and $\ce{I-}$, depend on the concentration ratio of $\ce{Hg^2+}$ and $\ce{I-}$, the following reactions can happen:
$$\ce{Hg^2+ + 2 I- ā¶ \underset{insoluble red ...
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0answers
40 views
how can I predict the rate of water ions precipitation on a surface?
Consider a titanium pot that contains 1kg water with the following ions:
$[Ca^{2+}]=22000$ ppm, $[Mg^{2+}]=1500$ ppm,$[Sr^{2+}]=791$ ppm,$[Na^{1+}]=48000$ ppm,$[Cl^{1-}]=120000$ ppm,$[SO_4^{2-}]=...
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2answers
111 views
Precipitation of AgCl from the tap water solution of the group 2 chloride
I had this question about an experiment where the group 2 chloride was dissolved in distilled water and excess $\ce{AgNO3}$ was added to the solution to form $\ce{AgCl}$ precipitate. One of the sub-...
0
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1answer
225 views
Is the water in an aqueous solution undergoing a reaction considered part of the system or surroundings?
System: In chemistry, a system is a chemical reaction. A system operates within its surroundings. Energy can move between the two.
Surroundings: The environment around a particular chemical reaction....
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4answers
306 views
How to get a precise answer to a textbook precipitation problem?
This question concerns a textbook problem* on precipitation. Briefly, there are $2\cdot10^{-4}$ of Mn$^{2+}$ and Cu$^{2+}$ ions in a liter of solution with $0.003$ M HClO$_4$. This solution is then ...
