Questions tagged [aqueous-solution]
For questions relating to compounds dissolved in water and resulting reactions and acid-base equilibria.
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Why doesn't frozen sugar solution taste sweet?
I'll try to make this as brief as possible:
Dissolved two teaspoons of table sugar (sucrose) in about 250ml water. Sipped it, and as expected it tasted sweet. I let the rest of it sit in the freezer ...
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Which "exotic salt" can lower water's freezing point by 70 °C?
The Medium.com article Mars Phoenix Lander, 10 Years Later shows several remarkable images and discoveries on Mars by the Mars Phoenix Lander circa 2008.
One image (shown below) shows what looks like ...
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Why do salts such as NaCl dissolve?
If we look at solubility of salts in water, we are told that they disassociate, because the positive $\ce{Na}$ ion is attracted to the partially negative oxygen in water and the negative $\ce{Cl}$ is ...
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Why is water "the universal" solvent?
This is an old question that our textbook tried to answer but worsened the situation.
Many things are soluble in water. So many, that studying solutions will always require studying aqueous ones. It ...
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Are all NO3- salts soluble in water? If so, why?
All the examples of $\ce{NO3-}$ salts are soluble in water (all that I know about).
Is it always so or there is some salt which doesn't dissolve in water?
If so what is the reason behind it?
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Why did the Rio 2016 pool water turn green?
One of the swimming pools at Rio 2016 Olympics has turned green:
While proliferation of algae is a likely culprit, there have been some alternative explanations offered by local organizers. CNN has ...
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Why is silver chloride less soluble than silver nitrate?
Related: Reaction between silver nitrate and aluminum chloride
Experimentally, $\ce{AgCl}$ is insoluble in water, but $\ce{AgNO3}$ is soluble. They're pretty common in a lab (well, $\ce{AgCl}$ is a ...
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What software can calculate aqueous solution equilibria?
What software is available out there to calculate the equilibrium in a set of reactions in aqueous solution? In particular, I'm interested in software general enough to simulate things like titration ...
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Is "Sulfuric acid... makes a poor electrolyte... very little of it will dissociate into ions" really true? What does that actually mean?
While researching chromate conversion coating for edits to this answer in Space Exploration SE, I came upon the following passage in Corrosion Resistance of Stainless Steel to Sulfuric Acid
Sulfuric ...
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Can other substances be dissolved in a saturated solution?
If I have a liter of water fully saturated with sucrose would it be possible to dissolve something like salt or any other substance in the water? Or when the solution is saturated, is it impossible to ...
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pH probe bulb - what is happening within the glass?
I am trying to understand how the glass bulb of a pH electrode of a pH meter works - the glass bulb itself. Not the reference electrode or the rest of the electrode (HCl, Ag/AgCl wire, etc...), the ...
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Why does solubility of solids sometimes decrease with temperature increase?
Recently I was researching $\ce{Ca(OH)_2}$, and I found this on Wikipedia:
\begin{array}{|c|l|}\hline
{\rm \color{blue}{Solubility~in~water}}
& {\mathrm{0.189\,g/100\,mL}\ (0\,^\circ\mathrm{...
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Hydration of H⁺ ion
I know that $\ce{H+}$ is not possible in water and it is present as $\ce{H3O+}$. But later on I come to know that even $\ce{H3O+}$ is not possible and that it is present as $\ce{H9O4+}$.
Why does this ...
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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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Why copper(I) is unstable in aqueous medium?
I am expecting that $\ce{Cu+}$ attains a $\mathrm d^{10}$ configuration by losing one electron from s-subshell. Since it has fully filled d-orbital, it should be stable. But it is found that it is ...
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Deliquescence/efflorescence: How can I convert between salt concentration and RH?
I am looking at two phase diagrams, one has axes of $T$ and $\%\ce{MgClO4}$ in a $\ce{H2O-MgClO4}$ mix, and the other has axes of $T$ and relative humidity. The authors of the second phase diagram say ...
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How much can the pH change through dilution?
Consider an acidic solution with Hydrogen ion concentration, $\ce{[H+]}$ of $10^{-5}\:\mathrm{M}$. Since $\:\mathrm{pH} = -\log \ce{[H+]}$ the $\:\mathrm{pH}$ of solution is $5$. Suppose we dilute ...
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Why does the graph of the electrical conductivity of sulfuric acid/water solutions have this knee in the ~85%-~92% range?
This answer to an earlier question regarding the electrical conductivity of sulfuric acid provides a graph showing the conductivity of sulfuric acid/water mixtures ranging from 0% to 100% sulfuric ...
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Why doesn't the boiling point of an aqueous solution depend on intermolecular attraction?
I understand that boiling point is a colligative property for aqueous solutions, and that it empirically depends on the mole fraction of the solute, rather than the identity of the solute. I ...
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Why does hand sanitizer turn into a liquid after coming out of the bottle?
Hand sanitizer is a gel in its bottle, but when I pour it on my palm, it turns into a free flowing liquid. Why does that happen?
It doesn't turn to a liquid when I pour it on my floor or my table. ...
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Is it possible to achieve a level of "truly zero" concentration? [duplicate]
If we take some aqueous solution and dilute it further and further, will the concentration of the solution ever get to zero? I would say no, simply because total dilution implies that all the ...
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If caffeine is an alkaloid, why is coffee acidic?
I have just put together on my mind these two facts: caffeine is an alkaloid and brewed coffee is slightly acidic (pH = 5).
My Biology teacher and my Chemistry teacher could not elaborate satisfying ...
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Copper Chloride: neutralizing and disposal
I plan on etching some PCBs with hydrochloric acid and hydrogen peroxide, which will therefore produce some kind of copper chloride (green color) which is highly toxic if released into the ...
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Why does Mg react vigorously in NaCl solution and less so in water?
When you put $\ce{Mg}$ into water a few $\ce{H2}$ bubbles appear. But when you put $\ce{Mg}$ into a $\ce{NaCl}$ solution there is a vigorous release of $\ce{H2}$, why is this and what reactions are ...
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Why are synthetic pH indicators used over natural indicators?
Synthetic indicators seem to be exclusively used when determining the pH of a substance with an indicator (with the exception of that school experiment where you boil cabbage to demonstrate natural pH ...
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Should bromine water be called a solution?
Bromine water is a reagent which is used to test for unsaturation in organic compound. It is $2.8~\%$ bromine in water. In many places, it is refer to as bromine solution.
But it is observed that ...
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Why does the ionic product of water remain constant after addition of non-neutral solute?
In my textbook, it is given that the ionic product of water $K_\mathrm{w}$ remains constant even when a non-neutral solute such as an acid is added to it.
$$K_\mathrm{w} = \ce{[H3O+][OH-]}$$
When a ...
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Do azeotropic mixtures evaporate proportionally?
Do azeotropes evaporate, without boiling, in proportionate amounts, or does this property describe their behaviour only at boiling point?
Concretely, if 91% isopropyl alcohol/water (by volume, i.e. an ...
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What might serve as an initial starting photocatalyst for this large water-splitting solar simulator?
Question: What might serve as an initial starting photocatalyst for this large water-splitting solar simulator? Surely there must have been some planned experiments!
The Gizmodo article Insane Light ...
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Reaction mechanism in fluoride adsorption to aluminum oxide
Despite a fair amount of research (excluding non-open access journals, to which I have not got access), I cannot seem to find an explanation of the process that takes place when $\ce{F^-}$ adsorbs to ...
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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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Would sodium explode in salt water?
I’ve seen the video etc of sodium being put into freshwater and the reaction of flames/small explosion but I wonder if the same reaction would occur if conducted in salt water such as the ocean.
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Why is it not dangerous to dissolve NaCl?
$$\ce{H2O~(l) + NaCl~(s) ->[\Delta] Na+~(aq) + Cl^{-}~(aq)}$$
When table salt is placed in water, it dissolves due to the polarity of water molecules. When solvation takes place, negatively polar ...
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Is there any electronic component to water conductivity?
Answers to Decrease in temperature of a aqueous salt solution decreases conductivity indicate that the electrical conductivity of salt solutions arises from the mobility of ionic species and therefore ...
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Water exchange at Al (III)
Why is the rate of water exchange at Al(III) centres so slow ?
According to this medical book (p.5) it is $10^{5}$ times faster at Mg(II).
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Does the mass of sulfur really decrease when dissolved in water and increase when burnt?
I was going through a bunch of interesting science 'facts' and one entry went this way:
Name an element whose mass decreases when it is dissolved in water and increases if it is burnt.
I tried ...
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Why are indicators used only in the form of dilute solutions?
Why are indicators used only in the form of dilute solutions? I get that indicators are a form of weak acids themselves, and the extent of their dissociation varies with the pH of the solution they ...
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Is there oxygen isotope exchange between dissolved CO2 and H2O?
If you had a sample containing an elevated concentration of $\ce{H2^{18}O}$, and bubbled $\ce{C^{16}O2}$ through it, would some of the oxygen-18 isotope be transferred from water to carbon dioxide?
I ...
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Acid-base equilibrium of NH4CN
I'm having difficulties understanding this problem.
We have in the problem that $K_\mathrm a$ for $\ce{HCN} = 6.2\cdot10^{-10}$ and $K_\mathrm b$ for $\ce{NH3} = 1.8\cdot10^{-5}$.
Write chemical ...
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Vapor Pressure Paradox
This is quite an interesting situation I had thought of. Consider two beakers, each containing $\pu{180 g}$ of water. Also, suppose one of the two has $\pu{1.8 g}$ of glucose dissolved in it. Let's ...
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Relative acidity of aqueous LiF, SnCl2, and YCl3
Which one of the following salts make the highest and lowest pH when dissolved in water?
$$\ce{LiF, SnCl2, YCl3}$$
My approach was :
considering the corresponding aqua acids, the order of acidity ...
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Are all solutions of weak acid/bases buffers?
I am having a difficult time understanding what makes a buffer a buffer.
Buffers in my textbook are defined as a solution of a weak acid or base and their conjugate acid/base. So if I were to just ...
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Can sodium bicarbonate be considered an acid?
I was reading about acids and bases today and finally decided to question the statement that "baking soda is a base."
Let's start with the dissolving of baking soda, $\ce{NaHCO3}$. The equation to ...
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How does the HCl-KCl Buffer work?
I have just been studying the $\ce{HCl}$-$\ce{KCl}$ 'buffer', but there are still quite a few things I am uncertain about. I would appreciate any help in clearing up some questions I have.
What I ...
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Why do some substances ionize instead of dissolving in water?
My question can also be understood as
what make something electrolyte or nonelectrolyte?
I think this question stems mainly from my confusion with the definitions of ionizing and dissolving.
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Details of what actually happens in cold sulfuric acid between 80 and 90%; what molecular changes cause the viscosity to skyrocket?
AChem's answer to Why does the graph of the electrical conductivity of sulfuric acid/water solutions have this knee in the ~85%-~92% range? includes this plot from Horace E. Darling in "...
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How to derive the conductivity titration curve which accounts for salt formation
I derived an equation that gave me the volume of base required to get a certain $\mathrm{pH}$:
In a titration between a weak acid $\ce{HA}$ and weak base $\ce{B}$ (adding base into acid solution) the ...
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Why aren't the copper(II) ions in CuSO4 precipitated by hydroxide ions from water?
From my own experience and literature, I know that $\ce{CuSO4}$ is well soluble in water and dissociates into $\ce{Cu^2+}$ and $\ce{SO4^2-}$. $\ce{Cu(OH)2}$, however, is not: $K_\mathrm{sp} = 2 \cdot ...
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Solubility of gold salt solution?
I was wondering what salts of gold are soluble and which are insoluble. From what I understand, silver is soluble as silver nitrate but insoluble as most other common salts like chlorides and ...
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Why is there a decrease in the total volume when NaOH dissolves in water?
When a solute is added to a solvent, the volume of the solution should be equal to the sum of the individual volume of the solute and solvent (i.e total volume), right? But why is there a decrease in ...
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