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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5
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1answer
431 views

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 ...
3
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1answer
110 views

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 ...
3
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1answer
11k views

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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2answers
3k views

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 ...
5
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1answer
1k views

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 ...
3
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1answer
788 views

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 (...
2
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1answer
951 views

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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1answer
30k views

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/...
3
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1answer
259 views

When are we justified in making assumptions in questions

The density at $20^\circ\mathrm{C}$ of a $0.500~\mathrm{M}$ solution of acetic acid in water is $1.0042~\mathrm{g/mL}$. What is the molality of the solution? The molar mass of acetic acid is $M(\ce{...
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2answers
13k views

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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1answer
84 views

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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1answer
130 views

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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2answers
69 views

Adding concentrations to obtain mass

I have a question that gives two concentrations and asks for the mass of HCl formed by the reaction. I have two concentrations: 250mL of 4.00M $\ce{H2SO4}$, and 250mL of 1.00M $\ce{NaCl}$. Here is ...
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1answer
1k views

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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0answers
100 views

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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3answers
2k views

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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2answers
196 views

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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2answers
384 views

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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3answers
8k views

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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1answer
2k views

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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2answers
13k views

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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1answer
79 views

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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1answer
2k views

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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1answer
6k views

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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1answer
328 views

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 ...
3
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1answer
155 views

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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3answers
7k views

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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2answers
13k views

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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2answers
2k views

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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2answers
318 views

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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1answer
2k views

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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1answer
368 views

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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2answers
440 views

what is a clear liquid that attacks cellular respiration

I'm doing a biology assignment and need to find out a clear liquid that attacks cellular respiration. It needs to be toxic and either absorbed through the skin or inhaled.
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2answers
271 views

Can a 2,4-dinitrophenol aqueous solution be a clear liquid?

I'm trying to figure out a murder mystery assignment for my biology class and in the scenario we're given a clear liquid is thrown on someone. I'm trying to find the chemical and the only thing making ...
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1answer
858 views

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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1answer
2k views

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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1answer
2k views

Concentrations of mixed solutions

If I mix a $\pu{2 M}$ solution with a different $\pu{1 M}$ solution, do the individual solutions reduce in molarity to $\pu{1.33 M}$ and $\ce{0.33 M}$ respectively?
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3answers
26k views

How is langmuir's adsorption isotherm different from Freundlich's

I see no difference between the two,both say that degree of adsorption reaches a limiting value at high pressures and at very low pressures degree of adsorption is directly propotional to pressure. ...
5
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1answer
312 views

Standard solution and extracted solution : same concentration?

Summary : I am currently testing how a certain type of foam adsorbs HAP, PCB and OCP, and to this end I am depositing some on the foam, then extracting it. To know how much was extracted, I need to ...
10
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4answers
6k views

Why do solutions become saturated?

Why can a solvent dissolve only a particular amount of solute? If we add more solute to the solution, the number of solute particles in contact with water increases. So rate of dissolution should ...
4
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3answers
5k views

Does rate of Evaporation change with surface area?

Two vessels of the same volume, in the same location and open to the atmosphere. One is of a small diameter, the other is of a larger diameter. The question is will the vessel with the larger surface ...
4
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2answers
66k views

What is the differences between partial pressure and vapour pressure?

Was looking at Henry's law and Raoult's law constants and there seemto be lots of equations involved. Henry's law involves partial pressure and the latter involves the vapor pressure. Wondering what ...
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5answers
40k views

Difference between solubility and dissolution?

How is solubility different from dissolution? And how are they both different from solvation?
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1answer
4k views

why are Ca(OH)₂ and Al(OH)₃ less soluble than Na(OH) in water

Even though it has more $\ce{OH}$ groups and still it is very weak in terms of dissolving? please clarify to me in terms of polar and non polar solubility, how to determine whether a compound is ...
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1answer
9k views

What is an equivalent?

I want to know what is an equivalent and how is it different from equivalent mass. How to calculate and why is it used in chemistry for knowing concentration?
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1answer
13k views

Why is M1*V1 = M2*V2 only used for diluting solutions?

Why is $M_1V_1 = M_2V_2$ only used for diluting solutions? Why can it not be used to figure out how many moles to add to make a solution more dilute?
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1answer
1k views

Converting sulfate ion to sulfur trioxide?

I have a solution of only sulfate ions (no other positive ions belonging to the sulfate ions, because the positive ions are attached to the intermediate in a catalytic reaction). I want to convert ...
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1answer
2k views

Mole fraction of solute of a dilute solution

According to our book, when the solution is dilute, the mole fraction of solute can be given as: X2 = molality (m) x mass of solvent (M1) / 1000 Actually it is written as: X2 = m/(1000/M1) How is ...
8
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1answer
245 views

How does shock trigger nucleation of gases dissolved in a liquid?

When you drop a bottle of soda, the dissolved $\ce{CO_2}$ starts nucleating. Opening it before it's 'settled' will trigger more nucleation and usually makes a mess. Why does the shock trigger ...
4
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1answer
12k views

Deviation from Raoult's law because of adhesive and cohesive forces

A solution made of two or more compounds have adhesive and cohesive forces. Cohesive forces are the attractive forces between the same molecules. Adhesive forces are the attractive forces between ...