Questions tagged [aqueous-solution]
For questions relating to compounds dissolved in water and resulting reactions and acid-base equilibria.
1,159
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Why is my battery of galvanic cells not enough to power a lamp rated for a lower voltage than the battery provides?
I made a series of 12 galvanic cells with saltwater as an electrolyte and zinc and copper as electrodes. It produces 8.8 V, but it can't even light a 2.5 V bulb.
Please assist in understanding what ...
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Which one is more stable in aqueous solution Cr3+ or Ti4+? [closed]
Cr3+ has a half-filled configuration but Ti4+ has a noble gas configuration. I have seen many people answer that Cr3+ is more stable without any proper explanation.
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Exhaustive explanation of all electrochemical processes occurring during electrolysis of copper sulfate solution
I’m trying to gain a comprehensive understanding of what chemically occurs during the electrolysis of copper sulfate solution using copper electrodes.
Some resources say only copper is deposited on ...
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Purifying ferrous sulfate
For my wood staining experiments I have purchased 1 kilo of ferrous sulphate as a source of iron(II). It turned to be quite oxidised (yellowish) and the its solution is muddy yellow instead of green. ...
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How to find pH for acetate buffer?
Calculate the pH of the solution that results when $\pu{40.0 mL}$ of $\pu{0.100 M}$ $\ce{CH3COOH}$ is mixed with $\pu{30.0 mL}$ of $\pu{0.200 M}$ $\ce{NaCH3COO}.$ $K_\mathrm{a}(\ce{CH3COOH}) = \pu{1....
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How does CO2 'dissolve' in water (or blood)?
I'm trying to understand CO2 dissolved in blood, carbonic acid and the bicarbonate ion. I think of 'dissolving' as in NaCl dissociating into Na+ and Cl- ions sloshing around in water. CO2 isn't ...
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Misconception regarding mean ionic activity coefficient and applying it to equilibrium constants
I probably have some simple misconception about the mean ionic activity. The mean ionic activity coefficient is defined as
$$ \gamma_{\pm} = \sqrt[^{p+q}]{\gamma^p_+\gamma^q_-} \tag{1} $$
I'm just not ...
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Why does copper(II) sulfate solution turn black on addition of excess sodium borohydride?
In my laboratory experiment, I was supposed to reduce copper(II) sulfate to copper by means of $\ce{NaBH4}$, an indication of which was supposed to be a colour change from blue (copper(II) sulfate) to ...
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Determining iron(III) content in mixture of iron(II) and iron(III) [closed]
Problem
Outline a plan of an experiment to determine the percentage of iron present as iron(III) in a solution containing $\ce{Fe^3+(aq)}$ and $\ce{Fe^2+(aq)}$ ions. You are provided with zinc, a ...
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Is adding chelating agents to nutrient solution useful?
I'm using a hydroponic system with a fertilizer whose micronutrients are chelated with EDTA. The stability range of EDTA lies between PH 4-6.2. Due to a recent optimization of the fertilizer regime ...
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Water Vapor Permeable Membranes
Could someone recommend a vapor-permeable membrane that allows passage of water vapor and air but not liquid water or any other solution?
I am trying to maintain the relative humidity of a thermally ...
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Combined solubility of three solutes in water
I am trying to find a way to calculate the saturation point of a combination of sodium carbonate, sodium sulfate, and sodium hydroxide in water at 60 degrees C. Is there a way for me to do this? To ...
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What happens during a displacement reaction? [closed]
When Zn metal is added to a solution of Cu(II)SO4, Zinc displaces Cu to form ZnSO4 as Zn is more reactive than Cu. What I don't understand is how.
1- What I'm assuming is: Zn metal collides with [SO4]...
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How to remove oil/grease contaminant from an aqueous solution?
I have a solution of water and calcium nitrate that is contaminated with some sort of heavy petroleum oil, semi-solid at room temperature a bit like petroleum jelly, and a strong odor of very crude ...
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Isolating potassium chloride from sodium chloride and potassium hydroxide
Assume that you have an aqueous solution of sodium chloride and potassium hydroxide. Is it possible to isolate potassium chloride from this?
I'm thinking about the following:
Na+(aq) + Cl-(aq) + K+(aq)...
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How to find ion concentrations at various points in a solution that will precipitate multiple insoluble salts?
The solubility product constant of lead (II) iodide is $1.2 \times 10^{-5}$ at 273 K.
The solubility product constant for lead (II) carbonate is $1.5 \times 10^{-13}$ at the same temperature.
50 ...
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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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Discrepancies in using pOH vs pH to solve H+/OH- concentration change problem
I found an extremely confusing problem in one of the problems we did in class for general chemistry. This was the question:
How many moles of $\ce{H3O+}$ or $\ce{OH-}$ must you add per liter of $\ce{...
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What is the resulting solution after leaching hardwood ash with water?
After doing online research, I've noticed there are differing interpretations on what happens when ash is mixed with water, so I've come here seeking clarification on what indeed happens, and also ...
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Does hypochlorous acid oxidize hydrogen peroxide?
The following reaction is from https://ncert.nic.in/textbook/pdf/kech202.pdf, p. 11:
$$\ce{H2O2 + HOCl -> H3O+ + Cl- + O2}$$
I have to find if $\ce{H2O2}$ is acting like a reducing agent or an ...
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What is the effect of adding another solute to the solubility of the initial solute?
Let's say we have a saturated salt solution with 35 g/100 mL NaCl in water. If we add another solute up to its saturation concentration, for example 182 g/100 ml sucrose (C12H22O11), what happens?
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Is boiling aqueous solution of copper(II) sulfate safe?
I want to create saturated coper(II) sulfate solution in order to grow crystals. Is boiling a solution of copper sulfate at home safe? Are there any risks? Is the vapour pure water?
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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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I spilled some .1M Copper Sulfate on my sweater [duplicate]
I have accidentally spilled some .1M solution of Copper Sulfate (CuSO4) on my white cotton sweater. It left a light blue stain and I’m wondering how I might successfully remove the stain from the ...
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Adequate emulsifier for dimethoate
Dimethoate is a broad-spectrum systemic insecticide and miticide. It is sold for example as Drexel in the US or as Danadim in Australia (there are many others, Rogor, etc).
The formulation from Sico ...
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Chemical Equilibrium of the Esterification Reaction Between Propanol and Ethanoic Acid
I am trying to investigate the relationship between temperature and equilibrium constant of the esterification reaction between propanol and ethanoic acid in reflux system, with conc. sulphuric acid ...
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Why ppm500 water TDS scale is used and how accurate it is?
So, most TDS meters, it seems, uses this scale.
To qoute:
The conversion from EC to ppm is as follows:
ppm500 = EC x 500
ppm700 = EC x 700
Some examples of how ...
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Which single parameter can tell about the absolute as well as relative position of a solvent wrt a specific polymer in Hansen Space?
I am trying to represent solutions of a specific polymer (let's say PVDF) dissolved in various solvents using a single parameter. By various solvents I mean single solvent (e.g. DMF) or solvent blends ...
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Selective Removal of Sodium Acetate
I am currently working on an extraction and synthesis of sodium salicyate from acetylsalicylic acid and sodium hydroxide. After doing a liquid-liquid extraction from DCM, using a sodium hydroxide ...
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Can titanium dioxide oxidize sulfite
Suppose that there is 100mL of a 1M SO2 solution in water. If 1g of TiO2 photocatalyst is dispersed throughout the solution and UV light is shined on it, would it cause significant amounts of the ...
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Sodium Chlorite Listed as Active Ingredient in Anti-Fungal/Anti-Bacterial Fish Medication
My hobby is Fish Keeping. About 6 months ago I picked up a medication called Maracyn Oxy. It's a non-antibiotic treatment for true fungal and some bacterial infections and it works like an absolute ...
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Incompatibility of Helmholtz Double Layer and Redox electrochemistry
In an electric double layer capacitor(EDLC) (or any situation with a Helmholtz double layer) what prevents the ions from being reduced or oxidized like the ions in an electrochemical cell?
If it is ...
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Solubility of multiple solutes and limits of solubility during freezing
I'm interested in modeling the freezing of solutions of water and I'm not really sure what happens in water after the solubility of a given material is reached. I know that as ice crystals form they ...
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Recovery of Urea from aqueous solution [closed]
When adding Urea to water, the reaction is highly endothermic. I was playing with the idea of using that for a Desktop cooling system, but for that, I'd of course have to recover that Urea from the ...
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How to extract pure carbon dioxide from sodium bicarbonate?
What are the most commonly-used methods for extracting carbon dioxide gas from an aqueous solution of sodium bicarbonate?
Several industrial "Carbon Capture" plants today are able to extract ...
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Creating HCl acid [closed]
I have the following reaction:
$$\ce{2 AlCl3 + 3H2O -> 2 Al(OH)3 + 6 HCl}$$
My goal is to create hydrochloric acid, but for the reaction shown, hydrochloride gas is produced instead. There are two ...
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How to calculate pH resulting from dissolving a salt in water? [closed]
The main question is how to calculate the changes in pH after dissolving a salt in water.
Suppose we dissolve 1 gram of magnesium carbonate (MgCO3) in 1 liter of Water. This will result in (...
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Finding dissolved amount of base from pH and solubility product
Calculate the amount of $\ce{Mg(OH)2}$ which is solubilized in $\pu{1.25 L}$ of a buffered solution at $\mathrm{pH} = 9.5$. $(K_\mathrm{sp}(\ce{Mg(OH)2}) = \pu{5.61E-12})$.
From $\mathrm{pH}$ I ...
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Nature of Bisphosphonates Binding onto Hydroxyapatite in the Aqueous Phase
In many studies I've read, bisphosphonates (first image) are said to bind remarkably onto bone hydroxyapatite (second image) crystals. It was reported by J. Roelofs et al., (2008) that this mechanism ...
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Why is supersaturated sodium acetate so (meta)stable?
Sodium acetate is a common example used in general chemistry lectures to illustrate the idea of supersaturation, and that precipitation of a supersaturated solution can be initiated by a seed crystal. ...
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Can addition of a "neutral" salt like NaCl assist pH test strip measurement accuracy in low ionic strength/poorly buffered solutions?
After a web-search, it seems ISAs (Ionic Strength Adjusters) are offered commercially to assist pH electrode/probe measurements. Presumably meant to increase conductivity (without affecting pH ...
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An Index Poisoning Case Involving Dichlor and Carbonic Acid [closed]
I'm currently working an unusual case of poisoning, with Sodium Dichloro-S-Triazinetrione.
In my case, I need to know the expected reaction with carbonic acid.
I'm also curious if anyone could give ...
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what happens to the electrons in low-voltage conductivity of salt water [closed]
Suppose you take a 100 millivolt voltage source, and connect it using a pair of copper wires to a bath of salt water.
A current will flow through the water. If I'm not getting things completely wrong, ...
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Can 5% sulfuric acid and 3% hydrogen peroxide form piranha solution?
I'd like to use 5% sulfuric acid and 3% hydrogen peroxide as an etching solution for copper. (In the past I've used dilute hydrochloric acid and hydrogen peroxide but the generation of chlorine gas ...
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Solubility of nitrogen dioxide in sodium hydroxide
I know $\ce{NaOH}$ can absorb $\ce{NO2}$, but I could not find any data of solubility of $\ce{NO2}$ in $\ce{NaOH}$ at room temperature and atmospheric pressure.
I am trying to figure out how much NaOH ...
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Reaction between hydrobromic acid and sodium borate
Write the reaction for a a sodium borate solution being titrated by hydrobromic acid, assuming sodium borate is represented by $\ce{Na3BO3(aq)}$.
I think this is a simple double replacement reaction:
...
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how dilute should the solution be for a noticeable enough colligative property such as relative lowering in vapor pressure?
I was mixing soup powder with boiling water today and noticed the vapors coming from the water suddenly vanish; seemed like the powder being non volatile decreased the mole fraction of water in the ...
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Is a diluted aqueous solution of sodium hypochlorite more stable than a concentrated solution, all else being equal?
On the Clorox website, they recommend that you dilute bleach (NaOCl) in water prior to use for disinfection. They say that you should make a fresh solution each time you need to use it, adding: “Don’t ...
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How is formula for mean ionic activity derived from its constituent activities?
I spent hours in order to understand the following - but without success:
At many places the mean ionic activity coefficient for the reaction
$$\ldots \rightarrow \nu_A A^{z_A+} + \nu_B B^{z_B-}$$
...
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How much salt in a cup of water would it take to neither hydrate nor dehydrate the average person? [closed]
I don't know a lot about chemistry, and this question came up during lunch with my friend. I was interested in this question so I thought I could ask here. Sorry if I didn't use the right tags.
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