Questions tagged [solutions]
This tag should be applied to questions dealing with solutions of any kind. A solution is a liquid or solid phase containing more than one substance where, for convenience, one (or more) substance(s) called the solvent is treated differently from the other substances, which are called solutes. If water is the solvent, then the more appropriate 'aqueous-solution' tag should (also) be specified.
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Difference between ideal & ideal-dilute solution
These two terms has been frequently used in Physical Chemistry by Atkins. He describes Raoult's Law using ideal solution while Henry's law using ideal-dilute solution.
I thought, at first they were ...
user5764
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Cold-sensitive magic pen
Yesterday, I bought some "magic" rollerball pens (those with water-based ink), available in red, blue and black.
They look and write like a normal pen, but have an eraser at the upper end, just like ...
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Is there a way to dissolve glue?
Background: I have a journal from my childhood. I applied glue (uhu brand. this one) to the papers almost 10 years ago.
Q: Is there a way to dissolve the glue and make the pages readable?
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Degree of association, van't Hoff factor and dissociation constant
$\ce{CH3COOH->CH3COO- + H+}$
\begin{array}{c|c c c}
\mathbf{Initial} & \mathrm{1~mol} & \mathrm{0~mol} & \mathrm{0 ~mol} \\\hline
\mathbf{Final} & \mathrm{1-\alpha ~mol}&...
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Is NaCl in water considered "solution" despite of NaCl's having some precipitation?
Is $\ce{NaCl}$ in water aqueous? For a certain amount of $\ce{NaCl}$, it can dissolve in water but if you add more $\ce{NaCl}$ it can't dissolve any more.
So, if in a certain reaction $\ce{NaCl}$ is ...
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difference between solving and dissolving something [closed]
What is the difference between the terms 'solve' and 'dissolve'? Up until now I have used the two terms interchangeably, not having any sound scientific definitions for each. I have thought them both ...
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How is dissolving a physical change and not a chemical change?
When salt dissolves in water it dissociates and it is no longer in a lattice structure. The electrostatic forces are no longer there and are replaced by water-ion interactions. To me that sounds like ...
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Are all homogeneous mixtures just solutions?
Or can there be a homogeneous mixture that is not a solution?
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What is the concept behind the calculations for the dilution of solutions?
I'm interested in the concept behind this computation and was wondering if anyone could give me some pointers or hints.
I've prepared $0.28~\mathrm{L}$ solution of $0.8500~\mathrm{M}$ of $\ce{Al(NO3)3}...
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Why there is no change in water level when salt is added?
Let us say we have one glass of water and after that when we add one or two spoon of salt then we notice that salt dissolves in it but when we measure the water level we found that there is no ...
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Are my protolysis equations right?
We had the task to solve several salts in water and measure the pH value of the solution. After that we should "create" the protolysis equation and to tell about Chemical equilibrium[s].
I get some ...
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Can a precipitate dissolve upon addition of a diluted acid?
Is it true that precipitates dissolve upon addition of diluted acids?
If a precipitates is dissolve , does it disappear from solution , or any thing else happened out there?
I am just curious ...
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About pH of an aqueous solution of SO2
Probably we can have an aqueous solution of $\ce{SO2}$ by dissolving it in water, because we would have an equilibrium between $\ce{SO2(g)}$ and $\ce{SO2(aq)}$:
$$\ce{SO2(g) <=> SO2(aq)}$$
How ...
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homogeneous mixture - Are they truly uniform in composition and proportion?
If 5ml alcohol is dissolved in 1 L of water ( the purpose is to highlight the low quantity of one of the liquids) , how is it possible for 5 ml to evenly dissolve in 1 L of water ? There is not enough ...
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Finding the mM concentration of capric acid (decanoic acid) in coconut oil
Im trying to figure out the mM concentration of capric acid in coconut oil. I know that There is 8% capric acid in coconut oil, but I would like to know how much capric acid is in coconut oil in a mM ...
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How to calculate the final concentration of calcium ions from known starting masses of carbonate and calcium ions? [closed]
If $\pu{50.0 mg}$ of $\ce{CO3^2-}$ and $\pu{50.0 mg}$ of $\ce{Ca^2+}$ are present in one liter of water, what will be the final (equilibrium) concentration of $\ce{Ca^2+}$ expressed in moles per ...
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solution concentrations [closed]
I think I'm making this more complicated than it needs to be, but here it is:
I have 7 drug solutions, all 1 mg/mL which need to have the following concentration in urine:
A: 25,000 ng/ml
B: 25,000 ...
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2
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CuCl2 dissolved in water
We dissolve $10\ \mathrm{g}$ of $\ce{CuCl2}$ in $0.1\ \mathrm{L}$ of water.
Given that:
$M(\ce{Cl})=35.5\ \mathrm{g/mol}$
$M(\ce{Cu})=63.5\ \mathrm{g/mol}$
How can one calculate the molar ...
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Do extreme homeopathic dilutions still retain quantities of the starting materials?
This Indian Institute of Technology Bombay press release quotes some research papers which claims to prove that homeopathic remedies do retain original substances even when diluted.
The paper ...
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Highest osmotic pressure
I’d like to ask a question and clear my misunderstanding.
Which of the following 0.01 M solutions have the highest osmotic pressure?
-$\ce{NaCl}$
-$\ce{C12H22O11}$
-$\ce{BaCl2}$
-$\ce{CO(...
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1
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Sugar dissolution test
Is there a way to detect whether sugar is completely dissolved in a cup of water other than looking at the bottom of the cup?
I was wondering if there is a test or something that can be carried out ...
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Supersaturation and Crystallization
I had a fairly simple question regarding supersaturation and crystallization. When a supersaturated solution is crystallized, is all of the solute crystallized or just the excess solute (such that the ...
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Mixing polar and non polar substances [duplicate]
According to the theory of London dispersion forces, intermolecular forces are created in non polar substances by induction of instantaneous dipole to neighbouring molecules. If that is the case then ...
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Differentiation between zinc, aluminium, and magnesium ions in solution
If I have three aqueous ionic solutions in which I know that the cation is $\ce{Al^3+}$, $\ce{Mg^2+}$, or $\ce{Zn^2+}$, how do I find out which is which?
I was thinking to add $\ce{OH-}$ in the form ...
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Periodically oscillating chemical reactions?
I've seen before chemistry demonstrations where solutions are mixed with one another and subsequently where the resulting product goes through periodic color changes: for example blue to orange and ...
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Reference request for the number of solvents around a solute [closed]
I want to know if there is a way to find number of solvent molecules that are directly embracing a solute molecule (something like a reference or table that shows waters of hydration).
Particularly I ...
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finding cation of unknown salt in solution from precipitate
I should probably add that I was originally given an unknown solid mixture of 2 salts. I separated the insoluble salt out by centrifuging and then decanting. I found that the insoluble salt is $\ce{...
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What elements and/or substances without water are liquid at room temperature? [closed]
I was thinking about liquids, and I started to wonder theses related questions:
1) Besides mercury, what elements are naturally liquid at room temperature?
2) What naturally found family of ...
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Debye-Huckel theory with non-polar solvents
I want to calculate the activity coefficients of mixed solvent salt solutions. I am seeing very strange behavior when I try calculating the activity coefficient of salts in non-polar solvents using ...
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Why the dilution of solvent doesn't affect the solid phase, in comparison to the liquid phase?
Dilution of the solvent adds new energy states to the liquid, but does
not affect the solid phase.
The above line appeared on the following page under the section "5: Colligative properties and ...
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Dissolving to Create a Solution with Ethanol
If at 95% Ethanol can dissolve chemical X at 1mg/1mL then theoretically if you have 500mg of chemical X you can dissolve it in 500mL of $\ce{EtOH}$ to get 1mg/mL correct?
My question is, if you have ...
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Given the concentration and density of a sample, calculate moles of bleach?
Given the concentration of bleach ($6\%\,\mathrm{m/m}$), density of bleach ($1.07\,\mathrm{g\,mL^{-1}}$), and molar mass of bleach ($74.44\,\mathrm{g\,mol^{-1}}$) how many moles of bleach are in a $4....
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Ink / formulation chemistry: What lab requirements
Little open information can be found on the requirements of the manufacture, development and testing of gel and printing inks.
It seems that most ink manufacturers have their own specific lab ...
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Proportion of gases filled in cylinder of sea-divers
In my book it is given that earlier cylinder were filled with 2% oxygen and 98% helium. Nowadays it is filled with 11.7% helium, 56.2% nitrogen and 32.1% oxygen.
There are few questions which come up ...
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Effect of impurities on enthalpy of fusion of ice
When I freeze water with some impurities (1% NaCl by mass), the mixture seems to have a much lower enthalpy of fusion that pure water. The impurities cause the freezing point to depress to 0.6°C. I ...
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Water in the ultrasonication bath
Why something jelly forms in the water if it is kept in in a ultrasonication bath for long periods?
When water is exposed to ultrasonication for say a month, some jelly substances form in the ...
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What would happen if I mix salt and sugar in a cup of water? [duplicate]
If I mix water in a cup with sugar at some stage the solution will become saturated and no more sugar will dissolve into the water. If I now add salt to the solution will the salt dissolve into the ...
Gobabis
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Can acid mine drainage form acid rain?
Can acid mine drainage form acid rain?
Since normal acid rain is formed via combustion of fossil fuels, the sulphur dioxide and nitrogen dioxide are all in the gas phase, whereas in acid mines the ...
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Henry's constant and solubility
According to Henry's law
The solubility of gas in a liquid is directly
proportional to the partial pressure i.e S=Kp
My book says that higher the value of K at a given pressure lower is the ...
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2
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Diluting acetic acid to obtain a solution of pH 5 [closed]
What percent of a solution needs to be acetic acid for a particular $\mathrm{pH}$? I have 100% acetic acid, and want $1~\mathrm{L}$ of solution with a $\mathrm{pH}$ of 5. I've done some research, but ...
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Cohesive Energy Density table request
Quick question: Any one knows a resource for Cohesive Energy Density of some organic materials ?
I am not looking for any specific molecule, actually I want to plan my project based on available ...
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Why do exothermic dissolution reactions occur?
I've always been taught that an exothermic dissolution means that the forming of solute-solvent bonds releases more energy than the energy consumed to break solute-solute bonds and solvent-solvent ...
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How to find the mass of a solute given a mass fraction? [closed]
How many grams of $\ce{CuSO4 * 5 H2O}$ are needed to prepare a $20\%$ (w/w%) solution of $\ce{CuSO4}$?
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Gibbs Free Energy of Solutes and Solutions
Using the equation $$\ce{CaSO4 (s) <=> Ca^2+ (aq) + SO4^2- (aq)},$$ and $\Delta H/\Delta S$ values, calculate $\Delta G$ at $50~^\circ\mathrm{C}$ when the solution is saturated with $\ce{Ca^2+}$ ...
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Alkaline glycine buffer molarity
Having never prepared a buffer solution before, I am hoping for a little help in understanding the process.
This method I plan to use calls for a $\pu{0.1M}$ glycine buffer at pH $10.6$. Some ...
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Can I make a pH 7 buffer from phosphoric acid and sodium hydroxide?
I am an electronics guy with not so much knowledge of chemistry.
I would like to prepare a pH 7 buffer to test pH meters.
All web references I have found so far describing how to make a phosphate ...
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Why does the molar conductivity decrease with increasing charge density?
This is a question in a problem sheet I have been set. Is it do do with the following equation: $\Lambda=\Lambda_0-a\sqrt c$? Surely charge density is proportional to concentration so therefore molar ...
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How to calculate the osmotic pressure of a sucrose solution?
The boiling point of an aqueous solution containing sucrose, $\ce{C12H22O11}$, is $101.45~^\circ\mathrm{C}$. Calculate the osmotic pressure of this solution at $35~^\circ\mathrm{C}$, at which the ...
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Computer killed by insecticide; what compounds are likely?
A friend of mine sprayed "Black Flag Home Defense" insecticide under her
computer. It died immediately. I'm trying to figure out why, and how
fixable it might be.
I found an MSDS, but it only says ...
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'Emulating' calcium hydroxide
I posed this question at the Seasoned Advice SE and thought I might get some more information here.
Traditionally prepared corn is cooked in a calcium hydroxide solution to make it more digestible, ...
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