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Questions tagged [aqueous-solution]

For questions relating to compounds dissolved in water and resulting reactions.

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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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How to set up equation for buffer reaction?

For buffer equations, how can you tell what to react with water? For example, if I have a 1 M acetic acid solution and 1 M sodium acetate solution (a conjugate acid-base pair) mixed together and am ...
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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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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 is AgCl less soluble than AgNO₃?

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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How can 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 according to Wikipedia. But how is it made? This link describes the procedure ...
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Stability 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 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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In my homemade electrolysis setup, only the negative end bubbles?

I've created an electrolysis setup by connecting a $6~\mathrm{V}$ battery to a cup filled with saline water via pencils; I am confused as to why only the negative pencil bubbles though. After running ...
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Is there a difference in the reactions of a dilute acid and a concentrated acid?

All of the exams that I've sat so far, and the homework questions I've had, always ask for the reaction between a substance and a dilute acid. Is there a difference in the reaction between a dilute ...
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Formation of MnO2 vs [Mn(H2O)6]4+ in aqueous solution

I am looking for reasons why $\ce{Mn(IV)}$ wouldn't be stable as a hydrate. I know that from standard reduction potentials it exists as a ppt of $\ce{MnO2}$, but what is stopping it from being a ...
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Can there be more solvent in a solute?

Something I know that leads to this question: Water dissolved in ethanol. It might sounds weird to say water as a solute. Textbooks always says that solvent is the one present in larger quantity. ...
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Why is potassium phosphate KH2PO4 in this reaction?

This is a continuation of this question because the first thing that came in my mind is that why potassium phosphate in this reaction is $\ce{KH2PO4}$ and not $\ce{K3PO4}$? In the wikipedia article ...
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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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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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How is hydration free energy of a solute measured experimentally?

I am reading a paper (Shirts, M. R.; and Pitera, J. W. and Swope, W. C. and Pande, V. S. J. Chem. Phys. 2003, 119, 5740-5761). Near the beginning of the paper (page 5745), the authors state: ...
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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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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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Is magnesium sulfate basic, neutral or acidic?

A question in my college test was whether $\ce{MgSO4}$ is neutral, acidic or basic. I was told to solve this kind of problem by hydrolyzing any ions that do not "come from" a strong acid or a strong ...
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1answer
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Vapor pressure of immiscible liquids

I have read that vapour pressure of a mixture of two immiscible liquids is $$P=P^0_A + P^0_B$$ where A and B are immiscible liquids. My question is, if they are immiscible, they would form separate ...
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Is H+ (in an aqueous solution) = H3O+? [duplicate]

I was learning about autoionization in science and my science teacher wrote $\ce{H3O+}$ as $\ce{H+}$ — now, my intuition would lead me to assume that: $$\ce{H3O+} = \ce{H+}$$ But, $\ce{H+}$ is just ...
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What is the colour of chromium(III) chloride solution?

I had a question asking about the colour of the solution of chromium(III) chloride in my exam, all my colleagues have different answers, I couldn't find any exact answer after searching!
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Is there a soluble salt, or compound that when dissolved in water results in a solution with density less than pure water?

Generally water soluble salts tend to 'fit between' the molecules of water such that the volume of the resulting solution does not increase much relative to the volume and added mass of the salt. So ...
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1answer
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Can I synthesize iron acetate like this?

The oxidation state of the iron doesn't matter too much; I am just trying to make an attractive red-brown ink. Here are some instructions I prescribed to a friend. Here's an approximately decent ...
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1answer
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Why do some solid chemicals dissolve better in colder water?

I just discovered that some solid chemicals, such as $\ce{Na2SO4}$, dissolve better in cold water than hot water from here and would like to know if there is any particular reason as to why. Is it ...
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1answer
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Saturation of multiple solutes

Can a liquid which is saturated with a single solute, dissolve a different solute, or is saturation a universal thing? I ask because I’ve seen that different solutes have different points (amounts) at ...
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1answer
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Acidic and alkaline salt solutions: why do some salt form acid/bases while others don't

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 ...
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0answers
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If both nitric acid and nitrate ion are stabilised through resonance, what makes the nitrate ion more stable in aqueous medium?

If both nitric acid and nitrate ion are stabilised through resonance, what makes the nitrate ion more stable in aqueous medium? Can the same argument be applied to nitrous acid and nitrite ion in ...
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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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1answer
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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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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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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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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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Preparation of iodine solution

How to prepare $\mathrm{0.1M}$ $\ce{I_2}$ solution. I have found in books that it should be prepared in $\ce{KI}$ solution but none of them explains why? Please explain in detail not just the ...
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Why doesn't water play a role in reactions in aqueous reactions?

$$\ce{Ba(NO3)2(aq) + Na2CO3(aq)}$$ In the above reaction both the substances are in water, however water plays no role in the reaction. Why is it that although water is present in the reaction, it ...
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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+} \...
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Reaction between alumina and aqueous sodium hydroxide, which one's right?

My chemistry textbook has a rather annoying irregularity. It cites two different reactions for the same set of reactants (aluminium oxide, sodium hydroxide and water) without the slightest mention of ...
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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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1answer
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Hybridization of Na in [Na(H2O)6]+

In the complex ion $\ce{[Na(H2O)6]+}$, the sodium cation forms 6 coordinate bonds with water ligands. Typically this octahedral form is associated with $\mathrm{sp^3d^2}$ hybridization as far as I ...
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Dissolve Silver Oxide

I was looking at how to dissolve silver oxide (in a solvent). I know that monovalent silver oxide will not dissolve in water, but are there any solutions in which monovalent silver oxide will dissolve?...
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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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1answer
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How could alcohol be made into a powder?

In the news recently is 'Palcohol', powdered alcohol, that you add to water or existing liquids to make it alcohol. Presumably this would dissolve and break apart into alcohol and {some other compound}...
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1answer
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Is there a way to calculate how fast water will cool?

Is there a way to calculate how fast water will cool if you know the water's starting temperature and temperature of the environment that you put it in, such as a freezer?
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Azeotropes and separation by distillation?

I have just recently learnt the theory of fractional and normal distillations and the basics of maximum and minimum boiling azeotropes. Most books say that the components of the mixture forming an ...
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Does dissolving salt in water change the pH?

I am particularly interested in the effect or lack of effect of dissolved NaCl in regards to pH in water. It would be interesting also if anyone has any insight for other salts and their effects. ...
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1answer
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Predicting pH of an acidic salt of an weak acid and weak base

Suppose we want to calculate pH of an $\ce{NH4HCO3}$ solution of known concentration. Now, $\ce{NH4+}$ will be hydrolised to give $\ce{H+}$ ions. Some $\ce{HCO3-}$ ions will be converted to (i) $\ce{...
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1answer
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Reaction of sulfate ion in copper sulfate electrolysis

I am planning to try copper plating a piece of metal by performing electrolysis on an aqueous solution of copper sulfate. I plan run an electrical current with the metal I want to plate as the cathode ...
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How to convert from w/w% to molarity?

After reading a number of explanations about it after googling, I'm a bit confused on this. Some explanations are doing it using a solution density, others aren't, though most are. On one site it's ...
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Entropy as the driving force for osmosis

How is entropy responsible for osmosis and is movement of solvent possible from its higher concentration to lower concentration? By concentration, I will be referring to the concentration of solvent ...
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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).