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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What chemical will dissolve the plastic coating on circuit boards
I'm trying to reclaim the metals on circuit boards and the vast majority is underneath the plastic coating. It is a brittle plastic that chips off in small flakes when etched but that process will ...
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In water, will sucrose be hydrolysed by water to form glucose and fructose molecules? [duplicate]
If I dissolve sucrose sugar ($\ce{C_12H_22O_11}$) in water, would the water readily hydrolyse the sucrose sugar to form glucose and fructose sugars?
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Kinetics of the conversion from metal oxide to metal hydroxide in water
How long can a metal oxide such as magnesium oxide remain in solution before being converted to the metal hydroxide?
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Can Ice Packs Freeze Water at 21 °C?
I receive $120~\mathrm{mL}$ bags of medicine in sterile water. The medicine is refrigerated and then packed with a significant amount of ice packs in an insulated bag. Generally three times the volume ...
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HCl/diethyl ether + Nitrogen?
Just wondering if anyone can tell me why bubbling nitrogen through a solution of $\ce{HCl}$/diethyl ether catalyst would remove said mix from my solution.
My current thought is that the $\ce{N2}$ ...
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When I dissolve sugar in my cup of tea/coffee, does it become a liquid?
When I dissolve sugar in my cup of tea/coffee, does the sugar go from being a solid to being a liquid?
Related: https://physics.stackexchange.com/questions/5562/what-keeps-the-sugar-suspended-in-the-...
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Which of the following elements forms a water-soluble, alkaline oxide?
An element burns in oxygen to form a solid oxide which dissolves in water. The pH of the resulting solution is greater than seven. Which one of the following could the element be?
A. sulphur
B. ...
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Can we determine apriori the volume of solvent in an electrolyte
Suppose I would like to create a one molar solution of NaCl in water. The molar concentration is defined as
$c_i=\frac{n_i}{V} $
$n_i=1$ in this case. I need to take 58.5 grams of NaCl (atomic ...
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What is the procedure to create stock solutions?
Until now to execute this recipe, each time i had to count those milligrams/Liter. An enough difficult procedure.
I am posting here this question to help me understand the procedure of creating ...
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Why is the water column empty in ICE table
In the ICE table pure solids and liquids have a value of one in the equilibrium expression but when we create an ICE table, why is the $\ce{H_{2}O}$ column empty? Should it not have a value of one?
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Volatile and non-volatile solutes in solution
What is the difference between having a volatile versus a non-volatile solute at the boiling point of the solution?
I have been getting mixed answers online concerning the differences outlined above. ...
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Mixing of powders to make stock solutions
For a solution such as:
Luria-Bertani (LB) Broth:
10 g tryptone
5 g yeast extract
10 g of NaCl ($M = 58.44\ \mathrm{g/mol}$)
q.s. to 1 l, pH to 7.2, autoclave.
I would like to make a bulk amount ...
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Solution, hardener and metal required to cast key duplicates
I just watched this YouTube video for a DIY key duplication system and was trying to figure out what all the material components could be:
The "mold solution" (parts 1 and 2)
The "hardener"
The "low ...
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Home-made way to detect lye in solution
I believe that electrolysis of salt water creates lye ($\ce{NaOH}$ - sodium hydroxide). In salt water, there's $\ce{Na+}$, $\ce{Cl-}$, $\ce{H+}$ and $\ce{OH-}$ as of ionts.
So at cathode, you get $\...
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How much does water expand when heated, and does salt affect that?
For this question, assume all things not mentioned are perfectly controlled, all at 14.7lbs of atmospheric pressure, and water is 100% pure of anything not mentioned, with no dissolved air.
Given a ...
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How does the Freezing Point fall in a solution?
It is known that addition of a non-volatile solute to a volatile solvent(liquid) to give a solution reduces the Vapour Pressure of the solution (well solvent actually as only solvent is volatile).
...
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Can a solid and liquid be miscible?
To be specific, what I mean is: is the following situation possible? At given temperature T, there are two substances, X and Y, such that pure X is a solid, pure Y is a liquid, and X and Y mix to form ...
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Residual stress in polymer coatings
A paper talks about the residual stress when coating polymers.
It says that residual stress is the sum of the "heat stress" (due to the difference in thermal expansion coefficients) and the "shrinkage ...
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What properties does a solvent with a high dielectric constant have?
My professor commented that water has a higher dielectric constant than alcohol.
Okay, but on what basis?
He didn't elaborate; he asked us which one seemed "more electric" and most answered water. ...
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why do we obtain a sigmoid curve in vapour pressure versus temperature graph
i have recently got a question in an assignment, which was somewhat like this
what would be the shape of curve obtained in a graph between vapour pressure & temperature of a binary solution in ...
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Byproducts of the neutralisation of hydrochloric acid with sodium hydroxide
Given a 1 M concentration of $\ce{HCl}$ and $\ce{NaOH}$ here are the pHs:
pH of $\ce{HCl}$: 1
pH of $\ce{NaOH}$: 13–14
and of course water has a pH of 7.
Here is a reaction that is most likely to ...
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Electric field effect on reactions
What would be the effect of putting a solution in a strong electric field? Would the reactions in the solution be affected?
I'm thinking yes – lots (if not all) – chemistry is dependent on charge (...
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High/low density water solution values
I would like to know what min and max values of densities are achievable with water solutions.
There are some conditions:
1. Normal or close to normal temperature;
2. Non-radioactive solutions/...
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Calculating the molar mass of a solute from freezing point
A $\pu{4.305 g}$ sample of a nonelectrolyte is dissolved in $\pu{105 g}$ of water. The solution freezes at $\pu{-1.23^\circ C}$. Calculate the molar mass of the solute. $k_f$ for water is $\pu{1.86 C/...
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When are we justified in making assumptions in questions
The density at $20^\circ\mathrm{C}$ of a $\pu{0.500 M}$ solution of acetic acid in water is $\pu{1.0042 g/mL}$. What is the molality of the solution? The molar mass of acetic acid is $M(\ce{CH3CO2H})=\...
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Why do ionic substances with higher lattice energies tend to be less soluble in water than substances with lower lattice energies?
I understand that that energy is required to overcome intermolecular forces holding solute particles together in the crystal, but I don't understand how this relates to lattice energies and respective ...
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Entropies of Solvation for Chlorate and Nitrate Anions
Can anyone find any data on the entropies of solvation for these two anions in water solution? I can't find any.
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How do I find a concentration from a sample tested on a spectrophotometer?
I have an assignment to calculate the concentration from a sample. The assignment is:
You have 100 µL of RNA. You take 10 µL from the sample and put it in 990 µL of water in the cuvette. The OD is 0....
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Finding the molarity of the combination of two solution reacting with each other
I have a question that gives two concentrations and asks for the mass of $\ce{HCl}$ formed by the reaction.
$$\ce{H2SO4 + NaCl ->Na2SO4 + HCl}$$
I have two concentrations:
$\pu{250 mL}$ of $\pu{4....
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Making a solution with two solutes
I need to make a solution that has a 15% (wt/wt%) HCl acid concentration and a 6% (wt/wt%) NaI concentration. I'm not sure yet how much of this solution I will be required to make so a general recipie ...
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Synthesizing monodisperse PbS quantum dots
For a research project, I am trying to synthesize lead (II) sulfide quantum dots using the method of Li et al.. I am injecting sulfur dissolved in 1-octadecene into a mixture of $\ce{PbO}$, oleic ...
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Why are solutions electrically neutral?
I keep reading that solutions are electrically neutral, but I've never read an explanation. I've read after the fact justifications, such as one problem which asked me to calculate the force of ...
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How can water with a very low hardness have substantial buffer capacity?
My freshwater fish tank has a pH of 5.8 and a KH value in excess of 40 or 720+ppm while still maintaining a water hardness of 20 ppm or GH< 1 now I am a math/phsyics student but I have taken both ...
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What solvent would have the fewest ions?
We know that water auto-ionizes (to a rather small extent).
My question is which solvent would have the fewest ions (or at least fewer ions than water).
I'm thinking that perhaps some kind of ...
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Why is a buffer solution most effective when concentrations of salt and acid are the same?
Why does a buffer work most effectively when the concentration of salt and acid is 1:1?
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Permanent suspension of cocoa powder into water
I have failed in permanently suspending cocoa powder into water. I have tried heat (212'f) and pressure (40 psi) into a sugar water solution (50/50). Also, powdered milk and evaporated milk have ...
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Thermodynamics adding salt to water changes the temperature
$5\:\mathrm{g}$ of an unknown salt are dissolved in $325\:\mathrm{g}$ of water. Both the water and the salt are initially the same temperature. The water's temperature falls by $11.4\:\mathrm{^\circ{}...
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Max Ionization Extent
How is this formula derived? What does it mean; what is the use of this formula?
I know that at infinite dilution, ionization extent should be very high because of Le Chatlier's principle.
But I'm ...
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Increasing mass
I'm watching a video, and the speaker states that the molality formula is better than the molarity formula because it is more constant, since molarity deals with volume and molality deals with mass. ...
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Titration of sulfuric acid with sodium hydroxide
$55.0~\mathrm{mL}$ of $0.250~\mathrm{M}~\ce{NaOH}$ is used to titrate $35.0~\mathrm{ml}$ of $\ce{H2SO4}$.
What is the molarity of $\ce{H2SO4}$?
I know that the equation for this reaction is:
$$\ce{...
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Condition for formation of azeotropes
Consider a binary azeotropic solution of two volatile components $A, B$. I wanted to try and find out the required concentrations of $A, B$ in the solution in terms of their vapour pressures. I tried ...
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metal salt solutions g/l means hydrate or anhydrous
I want to redo an experiment. They've used
Nickel chloride: 40 g/L
Nickel chloride can be bought in two forms: anhydrous ($\ce{NiCl2}$) and hydrate ($\ce{NiCl2....
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Why can't a potassium sulfate anion KSO4(-) exist in solution?
Please explain to me why $\ce{KSO4^-}$ doesn't exist as a molecular ion in (aqueous) solution. I couldn't find a reason why.
I assumed if you took one $\ce{SO4^{2-}}$ and one $\ce{K^+}$ ion, then ...
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Chemical Equation: Sulfuric acid and powdered sodium carbonate
I was asked to write a balanced chemical equation for the reaction between sulfuric acid and sodium carbonate. The balanced equation isn't the problem. The question asks to also show all the state ...
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Given the volumes: determine the pH and the final temperature of a mixture knowing only the initial pH and the temperature of the un-mixed components
I have a pretty basic question but the last time I took Chemistry was in 2007. I am studying the Navy's Nuclear study guide for their interviews and one of the question I am faced with is below.
...
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Does removing solution affect a supersaturated solution
Given a mixture of: a saturated solution of a solute in a solvent together with excess of the solute compound as crystalline material.
If one were to change the bulk composition of the mixture by ...
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Evaporation of a mixture of salts
I was wondering what happens when you boil dry a solution of several salts for example a solution of KCl and NaNO3. Since the ions dissociate I was wondering if the ions would combine randomly upon ...
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How much water has boiled off when precipitation begins? [closed]
Here's a challenge problem I created! None of my students could get it; can you?
$25$ grams of table salt (NaCl) is dissolved in $150$ grams of water. The temperature of the solution is raised to its ...
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Does the outcome of aromatic nitrations depend on the concentrations of nitric acid and sulfuric acid?
I came across a few equation and observed that when concentration of the $\ce{HNO3}$ and $\ce{H2SO4}$ with benzene ($\ce{C6H6}$) or its derivative varied the product changed. I did not perform any ...
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Why can we not use water instead of blank control solution in enzyme catalysis with Peroxidase experiment?
I have to do a lab about enzyme catalysis with peroxidase in my chemistry class. We are to use the blank control solution in the experiment. My question is, why can we not use water instead? I did ...
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