Questions tagged [aqueous-solution]
For questions relating to compounds dissolved in water and resulting reactions and acid-base equilibria.
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Changes of colour of sunset yellow in water
I am conducting an experiment on “sunset yellow (FCF)”.
Based on my observations, the substance, when in powder form, is bright red in colour (observed with naked eyes). When I dissolve the powder in ...
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what will happen if we add lithium cobalt oxide into water?is it true that molecule will break and lithium will make LiOH and CoO2? [closed]
I have tried to dissolve powder coated on cathode of lithium ion batteries.
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Theory that explains rate of absorption of a gas into a liquid?
What is the theory which explains how to calculate the rate of absorption of a gas into a liquid, assuming the gas is soluble in the liquid?
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Is avoiding chlorinated tap water for home ferments overblown? Anecdotal evidence on the internet says no, but what is the scientific consensus?
I originally thought about posting this in the Cooking StackExchange, but the chemical engineer in me starting to think this is more a problem of vapor pressure equilibrium and water treatment ...
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In self ionization of water, why do we write concentration of water in expression for equilibrium constant? [closed]
If we take self ionization of water, then water is a solvent so why do we write concentration of water in equilibrium constant? Can't it be product of concentration of H+ ions and OH- ions? In that ...
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How can we prevent retrogradation of starch?
Are there any additives which can prevent retrogradation of starch? I have prepared 13% of starch solution along with 2% of NaCl. The results were bit better. The synthesized gel was flowable with ...
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Small (personal) scale sea salt production?
I was looking to try to make a small setup for producing small amounts of sea salt. Ideally a series of evaporation chambers, with a heavy brine as the finished product, that could then be baked. May ...
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I'm writing a theory for a game called Timberborn, but I need help identifying a chemical from it [closed]
As the title says, I'm trying to write a theory for a game called Timberborn where I figure out the backstory of the game. But I need help identifying a chemical in the game. It's called Badwater, and ...
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dilution and pH and pOH
The question is: given a $10$ ml solution with pH = $12.3$, which is then diluted to a $100$ ml solution, find the pH of the new solution. My attempt was as follows:
[H$_3$O$^+$] = $10^{-12.3}$, and $...
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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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meaning of ingredient labelling `w/v`
A mouthwash states it has among other ingredients, menthol 0.042% w/v. What is the correct interpretation?
This chemistry.stackexchange.com answer says it's weight per volume with unspecified units, ...
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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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Numerically solving chemical equilibrium equations
Here are chemical equilibrium equations:
$\begin{cases}
\mathbf{N}^\text{T}\mathbf{X}+\mathbf{C}=\mathbf{Y}\\
\mathbf{N}\ln\mathbf{Y}=\ln\mathbf{K}
\end{cases}$
Here $\mathbf{C}=\begin{pmatrix}c_1\\...
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Creating 1L of 1000 ppb stock solution of Pb2+
I’m testing on samples that require a concentration of 1000 ppb (or 1 mg/L) of Pb 2+. My first thought was to simply dissolve 1 mg of Lead nitrate in 1 L of deionized distilled water to create 1 L of ...
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Variation of conductance of saturated aqueous solution with temperature
The following question was asked in JEE Mains 2020:
Let $C_{\ce{NaCl}}$ and $C_{\ce{BaSO4}}$ be the conductances (in S) measured for saturated aqueous solutions of $\ce{NaCl}$ and $\ce{BaSO4}$, ...
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How can the Kw of water be constant?
I know in neutral solution, $\ce{[H+]}= \ce{[OH-]}= \pu{1.0 x 10^-7}$.
However, let’s say I add an acid like HCl. This will increase $\ce{[H+]}$, therefore it’s no longer $\pu{1.0 x 10^-7}$, but is ...
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How to break down soap and detergents?
I am building a greywater harvesting system. It is a 3-stage system:
The 1st stage breaks down soap and detergents.
The 2nd stage filters the water.
The 3rd stage pumps water out of system.
What ...
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Preparation of copper carbonate from copper acetate and sodium carbonate
I reacted copper acetate with sodium carbonate. It formed a mixture of sodium hydroxide, copper carbonate, copper acetate, and copper oxide. I wanted to know if there is a process to remove the sodium ...
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What green and orange solids did I get when I mixed copper acetate and sodium carbonate?
I tried to make copper carbonate by mixing copper acetate with a sodium carbonate solution. I was expecting to see a light blue solid form at the bottom of the beaker and instead I found a green ...
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Store Palladium Chloride in Solution
I have one gram of palladium chloride ($\ce{PdCl2}$) and I want to use very small quantities of it, in milligrams somewhere. It is not possible for me to get my hands on a scale that can measure that ...
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When does "always add acid" not apply? [duplicate]
I've been taught a LONG time ago to AAA "Always Add Acid". I've recently come across what feels like an exception to that rule when making piranha solution (you add the H2O2 to the acid). I'...
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How to separate a mixture of sodium chloride and sodium hydroxide?
I recently did a double displacement reaction in which I formed a solution of water with sodium hydroxide and sodium chloride dissolved in it. Now I want to separate both of them. How can I do this?
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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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Why isn't mercury electrode used to produce commercial element sodium?
I know that while electrolysing a solution of brine, if we use mercury cathode, we get sodium amalgam instead of having hydrogen gas liberated. Even the Castner-Kellner process uses this to produce ...
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Why is the aqueous solution of KMnO4 slightly basic?
This is in the context of the various changes in oxidation state the permangananate ion can undergo with the variation of the pH of the medium. Besides the cases of strongly basic and strongly acidic ...
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How is an aqueous Ag+ the same as [Ag(H2O)2]+?
$\ce{Ag^{+}_{(aq)}}$ can be written as $\ce{[Ag(H2O)2]+}$ but how would you know that it bonds with 2 water molecules?
I don't get when ligands randomly form 6, 4, 2 bonds.
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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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How does a silver chloride electrode (Ag/AgCl) convert the potential in aqueous solution to the wire?
I am aware of the redox chemistry that happens at the electrode surface, but I'm not sure how exactly a change in electrical potential in the solution would change the potential in the electrode?
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HF and water miscible?
According to Wikipedia, HF is miscible with water. But isn't hydrogen fluoride a gas at RT and a sensible pressure? What would happen if you just kept adding more HF gas to some water?
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Would having a greater H-bond donor count make a substance more readily enter a twig?
Yes, weird plant scientist asking weird plant questions...
Background:
I am looking at how the twigs of trees absorb water, a poorly understood means by which trees alleviate water stress. Of 4 ...
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Possible technique for measuring pH in solutions
I would like to develop a device that measures pH in aqueous solutions. I'm not a chemist, but I have some basic knowledge about electrochemistry. So, I thought I could use two electrodes quite close ...
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Drying salts with HCl solution
I'm following a protocol from some old literature (1962), and I want to make sure I'm being safe. It asks you to dissolve some salts in 150 mL water + 25 mL concentrated HCl, then evaporate to dryness ...
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Is there any equation to predict the salting out concentration of a polymer?
I have to roughly calculate the salting out concentration of a polymer with respect to NaOH.
Is there any method to calculate?
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Can we add specific conductivities at any concentration?
Suppose we have specific conductivities of $\pu{0.1 M}$ $\ce{K+}$ and $\pu{0.1 M}$ $\ce{Cl-}$. Can we add their specific conductivities to get specific conductivity of $\pu{0.1 M}$ $\ce{KCl}$?
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Why is the specific gravity of 0.9 % saline 1.0046?
Medical Normal Saline (0.9% Saline) contains 9 g of salt dissolved in 1000ml of water.
Hence a litre of NS should weigh 1.009 kg.
Hence its specific gravity should be 1.009, but it’s only 1.0046.
(I'...
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What is the name of the bond between oxygen atoms and Na+ ions when NaCl dissolves in water?
When NaCl (sodium chloride, table salt) dissolves in water, the NaCl molecules break apart. The hydrogen atoms form hydrogen bonds (I think?) with the Cl- ions. What is the name of the bond between ...
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Residue left after evaporation of a salt solution
When a salt solution is evaporated (bunsen burner, evaporating dish/beaker), for example CuSO4 aq, there will be residue left over, as with all salt solutions.
However, the common form of copper (II) ...
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Solubility of SrF2 in aqueous solution of NaF
This might be really simple question but I have no idea how to proceed to solve such kind of question.
The solubility product of $\ce{SrF2}$ in water is $\pu{8E-10}$. Calculate its solubility in 0.1M ...
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Reducing vaporization of concentrated hydrochloric acid solution
I have this bottle of hydrochloric acid solution. Although I do not know its concentration but I know it is quite concentrated. Every time I open it the fumes would get to all the places.
I have an ...
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Advice on forming a 10% solution of Maltol
I’m having great trouble forming a 10% solution of Maltol. Specifically, I’m trying to dissolve 3 grams of Maltol in 27 grams of solvent.
I’ve tried everything from Propylene Glycol, to Deionized ...
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Equilibrium Solubility of CO2 in Aqueous Solution and its Dependence on H3O+ Concentration
The equilibrium solubility of $\ce{CO2}$ in an aqueous solution is given by three chemical reactions:
$$
\begin{align}
\ce{CO2(g) &<=> CO2(aq)}\label{rxn:R1}\tag{R1}\\
\ce{CO2(aq) + H2O &...
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Sodium Citrate / Sodium Phosphate Buffer Calculations
I'm trying to work through the calculations of a specific paper (linked here / below) but, my numbers are way off and I can't get them to match for the life of me. I need to make the same buffer but ...
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Are all salts completely dissociated in solution when put in smaller amounts than their molar solubility?
From what I understand, the solubility is given in terms of molar solubility (or $\pu{K_{sp}}$), from which it can be easily calculated). Indeed, the saturation point represents the maximum amount of ...
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Reaction between concentrated sulfuric acid and sodium bromide
What are the products of the reaction between sodium bromide and concentrated sulfuric acid?
I did the question like this:
$$
\begin{align}
\ce{2Br- &-> Br2 + 2e-} \tag{R1.1} \\
\ce{SO4^2- 4H+ ...
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Scrubbing methanol and ethanol from a gaseous mixture
I have a gaseous mixture (air) at a temperature of approximately 30 degrees Celsius in which the following gases are present:
Oxygen 0 - 25%
Carbon Dioxide 0 - 20%
Methanol 0 - 100 ppm?
Ethanol 0 - ...
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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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Which one is nitric Acid, HNO3 by itself, or when it is included in H2O?
This is a quote from my Chemistry textbook:
Nitric acid ionises according to the following equation:
$$\ce{HNO3(l) + H2O(l) -> H3O+(aq) + NO3- (aq)}$$
I know that the formula for nitric acid ...
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Difference in calculated pH and the real pH of a phosphate buffer
I want to prepare a buffer system with $\mathrm{pH} = 7.00$ and a total concentration $c_\mathrm{tot} = \pu{0.10 mol l^-1}$ using sodium hydrogen phosphate $(\ce{Na2HPO4})$ and sodium dihydrogen ...
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What happens to a solute's potential energy during diffusion?
I was thinking, if you have a large amount of water, with an uneven solute concentration, diffusion will lead to an even concentration of solute throughout the solution.
Intuitively,that would mean ...
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Successive deprotonation - how far can it go?
It has been written that among the equilibria of the dissolution of $\ce{SO_2}$ in water, the dissociation of sulphur dioxide into $\ce{HSO_3^-(aq) + H_3O^+(aq)}$ is a complete dissociation. See the ...
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