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.

Filter by
Sorted by
Tagged with
3
votes
2answers
427 views

Dissolving in DMSO semantics

What does it mean when a substance (powder) is 'dissolved in DMSO and used at $\mathrm{5~\%}$' Does is mean that the substance is first dissolved in DMSO and then added to another solution where it ...
3
votes
2answers
2k views

Can dissolving be a chemical change?

My textbook says that $\ce{SO2}$ dissolving in water produces sulfurous acid, but that seems to be a chemical change. But $\ce{NaCl}$ dissolving in water is not a chemical change. Please explain.
3
votes
1answer
2k views

Acidic and alkaline salt solutions: why do some salt form acid/bases while others don't [closed]

I have a question regarding salts and their solutions. How come some salts, like sodium carbonate and ammonium chloride, produce acids/bases when dissolved in water? Moreover, how can you predict ...
3
votes
1answer
4k views

Is there a certain amount of titrant that is ideal?

For an AP chem lab dealing with determining the amount of citric acid in orange juice by titrating with NaOH, one of the discussion questions goes like this: Choose an amount of beverage to be ...
3
votes
3answers
3k views

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 ...
3
votes
1answer
881 views

Relation between freezing point depression and vapor pressure

My lab manual defines the freezing point as "The temperature at which the vapor pressure of the substance in its liquid phase is equal to its vapor pressure in the solid phase." It goes on to explain ...
3
votes
2answers
3k views

Why doesn't a buffer solution change ph(Appreciably?)

Consider a buffer solution containing weak acid $\ce{CH3COOH}$ and its salt $\ce{CH3COONa}$: \begin{align} \ce{CH3COOH &<=> CH3COO- + H+} \tag{1}\\ \ce{CH3COONa &-> CH3COO- + Na+} \...
3
votes
3answers
2k views

Proof of Dynamic Nature of Equilibrium

Here is how my textbook proves that dissolution of solid in liquid is dynamic in nature. It considers the example of a saturated solution of sugar. It says that, Though the solution is in ...
3
votes
1answer
6k views

Differences between miscible and soluble

What are the differences between soluble and miscible? So far I found this (page 3 http://faculty.sites.uci.edu/chem1l/files/2011/03/D01MANmiscibility.pdf): soluble=solid dissolves into a liquid ...
3
votes
1answer
2k views

How to derive van 't Hoff equation for Henry's law constant?

While studying about Henry's law, I encountered this equation: $$\frac{\mathrm d\ln H}{\mathrm d(1/T)}= \frac{-\Delta_\text{sol}H }{R},$$ where $\displaystyle\mathrm d(1/T) = -\frac{\mathrm dT}{T^2}$ ...
3
votes
2answers
9k views

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 ...
3
votes
3answers
4k views

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 ...
3
votes
2answers
2k views

What is hard and soft water and how does the process of dissolution work?

This is a very basic question about solubility, especially solution of table salt in water and solution of sugar in water. I have heard about terms like hard water, soft water, filtering of water to ...
3
votes
1answer
120 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
votes
1answer
822 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 (...
3
votes
1answer
40k 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
votes
1answer
432 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
votes
1answer
35 views

Energy required to break apart water molecules in dissociation?

I'm learning about the process of dissociation. I'm aware in dissolution that essentially three processes occur (I know I may be simplifying it, but I am in Year 11): Solute particles break apart (...
3
votes
1answer
116 views

Can we compare the vapour pressure of solutions whose concentrations and temperature is known?

If we have some solutions, in which we know the temperature and concentration of the solute particles, can we compare their vapour pressures? Original question: Which solution has the highest vapour ...
3
votes
1answer
76 views

Depression of the Freezing Point

Recently we learnt that there is a depression in the freezing point when a non-volatile solute is added to the solvent. Our teacher explained this phenomenon with a graph where the vapour pressure of ...
3
votes
1answer
943 views

Conductance of the mixture of two solutions with given resistance values [duplicate]

If $R_1$ and $R_2$ are the resistances of two solutions of equal volume what is the conductance of the mixture in the same conductivity cell? In general, I grasped neither the approach, nor the ...
3
votes
1answer
145 views

Flaw in my logic on Henry's Law?

It states mathematically $ p=Kx $ where $x$ is mole fraction of dissolved gas and $p$ is partial pressure of the gas. Dissolution of gases is exothermic, so with increase in temperature, solubility $x$...
3
votes
1answer
124 views

Is it possible to create a solution with superoxide?

I am not a chemist, and somehow I cannot find any material on this topic, so I decided to ask here. I am looking to create a solution with a specified amount/concentration of superoxide ($\ce{O2^.-}$)...
3
votes
1answer
1k views

Raoult's Law and Mole Fraction

Raoult's Law states that the partial vapor pressure of each component of an ideal mixture of liquids is equal to the vapor pressure of the pure component multiplied by its mole fraction in the mixture....
3
votes
1answer
410 views

Is a supersaturated solution still a solution?

Given that a solution must be a homogenous mixture, and having crystallized solids at the bottom of a solution is most definitely not homogenous, can a supersaturated solution still be technically ...
3
votes
2answers
10k views

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 ...
3
votes
1answer
325 views

Solve this mole fraction calculation with incomplete information

I am currently trying to solve a problem that seems quite simple at the beginning but the complexity reveals itself soon thereafter. The problem is the following: You mix a known mass of water ...
3
votes
1answer
28k views

Can you find the mass of solvent with mass of solute, volume of solution, and solution density?

If you have, for example, $\pu{10 g}$ of a solute dissolved into $\pu{100 ml}$ of a solution, and the solution density is $\pu{1.5 g ml^-1}$, can you just multiply $100\ \mathrm{ml} \times 1.5\ \...
3
votes
1answer
307 views

Why do acids usually completely react with bases?

When a neutralisation reaction happens, for example, $ \pu{100 mol l^-1}$ of $\ce{HCl}$ with $\pu{100 mol l^-1}$ $\ce{NH_3}$, why does all of the base and acid get converted to salt? Why isn't there ...
3
votes
1answer
3k 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 ...
3
votes
1answer
323 views

To calculate total vapour pressure of a solution

Question: 1 mole each of A and B were mixed to obtain an ideal solution of which one mole went to the vapour phase at equilibrium. If $P°_\mathrm{A} = \pu{100 torr}$ and $P°_\mathrm{B} = \pu{900 torr}$...
3
votes
2answers
3k views

How do we turn PTFE powder into a paste we can dilute in a solvent

We want to create a binder we can use in our filter elements that is PTFE based, so we need to somehow create a paste, we can thin down with a solvent that will still hold the PTFE in suspension, long ...
3
votes
2answers
835 views

Why is partial pressure used as a metric for oxygen in blood?

I know haemoglobin basically acts as an oxygen buffer. But when we talk about non-bound oxygen in blood (or water), we're referring to the amount of O2 in solution (aqueous state). From a biochemistry ...
3
votes
1answer
65 views

vertically growing icicle

I made some "super" soap bubbles with my kids using the following ingredients: liquid dish soap tap water corn syrup We left the solution out over night last night here in Maine and the temperature ...
3
votes
1answer
831 views

What happens when a semipermeable membrane allows only one solute to pass through?

I'm essentially a medical student where we deal a lot with osmosis. But when we are taught, it is done generally with only a single solute in consideration. What if two different solutes are used on ...
3
votes
2answers
4k views

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 ...
3
votes
1answer
1k views

Molecular weight determination from freezing point depression

Which is the better solvent for molar mass determinations by freezing point depression, benzene or cyclohexane? Which is the better method for molar mass determination, freezing point depression or ...
3
votes
1answer
113 views

Why is the maximal percent concentration of acids similar to their molar mass

Why is the usual percent concentration of a concentrated acid's solution similar to its molar mass? For example: ...
3
votes
1answer
4k views

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 ...
3
votes
1answer
158 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....
3
votes
1answer
909 views

What is the temperature needed for a reflux using a mix of solvents as the reaction medium? [closed]

I had a quick query regarding the setup of a reaction. The procedure that I am working from states that I need to put my reaction mixture under reflux for 3 hours. The solvents used are diethyl ether (...
3
votes
1answer
457 views

At what composition is Maximum deviation from Raoult's law observed?

Raoult's law states that in an ideal binary solution of two volatile components, the partial vapour pressure of each component is proportional to its mole fraction in the solution. A plot of total ...
3
votes
1answer
118 views

Is the mole fraction used in Raoult's law calculated initially or at equilibrium?

Raoult’s law states that: The partial pressure of any volatile constituent of a solution at a constant temperature is equal to the vapour pressure of pure constituent multiplied by the mole fraction ...
3
votes
1answer
1k views

Properties of azeotropes

Consider two liquids with vapour pressures in pure form being ${P^o}_A$ and ${P^o}_B$. ${P^o}_B >{P^o}_A$ which implies liquid B is more volatile. If the liquids formed an ideal solution, then a ...
3
votes
1answer
1k views

Why any non polar compounds dissolve in nonpolar substance like Benzene what is the reason behind it? [duplicate]

In case of ionic solvent the ionic solute dissolve in it because due to polar nature of water it break the bond between the ions through hydration energy and the ionic solvent dissolve in it. So I ...
3
votes
1answer
391 views

How to determine fire hazard of heating ethylene glycol to dissolve borax and boric acid

I am looking to replicate instructions provided in the last paragrph of this article that requires dissolving borax (Sodium Tetraborate decahydrate ($\ce{Na2B4O7·10H2O}$)) and boric acid in ethylene ...
3
votes
1answer
2k views

Finding out pKa of acid from molar conductivity

I'm reading about the electrical properties of solution where there is a problem like that: The molar conductivity of $0.0250\ \mathrm M$ $\ce{HCOOH(aq)}$ is $4.61\ \mathrm{mS\ m^2\ mol^{-1}}$. ...
3
votes
1answer
2k views

Electrode Potential at Equilibrium

At each electrode-electrolyte interface there is a tendency of metal ions from the solution to deposit on the metal electrode trying to make it positively charged. At the same time, metal atoms of the ...
3
votes
1answer
724 views

What does solubility limit mean in practical terms?

I am not really a chemist guy so please bear with me. Glycerol monolaurate has an upper limit of solubility in water of 20 μg/mL, which is enough for my experiment. Does this mean that no matter how ...
3
votes
1answer
654 views

Effect of nitrobenzene on solution UV/Vis spectra

I am wondering if there is a difference in the maximum absorbed wavelength of light if nitrobenzene is added to an acidic or basic solution. I've figured that resonance plays a part in some ...

1
3 4
5
6 7
18