Questions tagged [aqueous-solution]
For questions relating to compounds dissolved in water and resulting reactions and acid-base equilibria.
51
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Water based room spray [closed]
Hello I’m trying to mix essential oils to water and alcohol to create a room spray, unfortunately the oils rise to the surface and clog the atomiser pump.
Do you advise to use an emulsifier to the mix?...
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4
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1
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Why is my Ni or Fe cathode blackening and pores getting blocked during alkaline (6 M KOH) electrolysis?
I am conducting an electrolysis process for hydrogen $(\ce{H2})$ and oxygen $(\ce{O2})$ generation using a $\pu{6 M}$ $\ce{KOH}$ alkaline solution.
During the process, I have observed that my cathode ...
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3
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Experiment on pH vs Rate of Electrolysis - what do the results actually say?
My experimental setup looks at using different pH solutions (of $\ce{H2SO4}$ and $\ce{NaOH}$) for electrolysis of water with a Hoffman setup and then measuring the rate of production of gas (note this ...
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0
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How to dissolve a powdered drug once it has been mixed with water
For a biological experiment I have acquired $\pu{10 mg}$ of CHIR 99021 (laduviglusib). In order to obtain a $\pu{10 mM}$ stock solution, I had to dissolve the powder in $\pu{2.15 mL}$ of dimethyl ...
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2
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0
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Salts solubility and speciation calculations using PHREEQC
I am collecting data from literature for CO2 solubility in aqueous solutions. These are usually synthetic brines and are reported as molalities or wt% of salts or salt mixtures (I have NaCl, KCl, ...
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1
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What reaction takes place when ammonia and sulfur dioxide are introduced into barium chloride solution?
What reaction takes place when gaseous $\ce{NH3}$ and $\ce{SO2}$ are introduced into $\ce{BaCl2}$ solution and an insoluble white solid is produced?
I think that the white solid could be $\ce{BaSO4}$ ...
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2
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Does solubility product dictate predominant precipitate from the solution with several ionic compounds?
While removing temporary hardness through boiling, magnesium bicarbonate will give $\ce{Mg(OH)2}.$ $\ce{Mg(OH)2}$ predominates over $\ce{MgCO3}$ as the solubility product $K_\mathrm{sp}$ of $\ce{Mg(OH)...
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Do electrons really hang around the electrode while ions go take a swim?
This answer to this post addresses "what happens if you dip a single zinc electrode into some electrolyte solution." It explains that
However, though the zinc ion can diffuse through the ...
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Does Calcium Carbonate dissolve in an aqueous solution of sodium bicarbonate?
A countertop company (Wilsonart) advises the use of sodium bicarbonate to remove limescale (solid calcium carbonate) from the worktop surface. Acidic solutions are contraindicated because the ...
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1
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Why does balancing the oxidation of dichromate(VI) to chromium(III) require six iron atoms?
The problem:
Balance the following chemical equation using oxidation numbers:
$$ \ce{Fe^2+ + Cr_2O_7^2- -> Fe^3+ + Cr^3+} $$
What I have tried:
$$\ce{\overset{+II}{Fe}^{2+}(aq) + \overset{+VI}{Cr}...
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0
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Who is more polar: acetonitrile or methanol?
According to data dipole moment of acetonitrile is around 4 while that of methanol is 1.7 but is said that acetonitrile is more soluble in non polar solvent that methanol.
But shouldn't methanol be ...
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Stability of n-Dodecyl-beta-D-maltoside in buffer solutions for assay experiments
I have a buffer system which contains multiple salts and in addition DTT and n-Dodecyl-beta-D-maltoside.
I understand that DTT is hydrolysing quite fast and this component must be used always fresh ...
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2
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2
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In an unsaturated solution, is the product of ions still equal to Ksp?
Suppose I have a solution of a sparingly soluble compound, and consider its solubility in g/L. If I have less g/L of solution than that amount, it means the solution is unsaturated, but what happens ...
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2
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2
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My textbook writes hydronium ion as [H(H2O)]+, is this correct? [closed]
[...] Thus, it bonds to the oxygen atom of a solvent water
molecule to give trigonal pyramidal hydronium ion, $\ce{H3O^+}$ $\ce{\{[H (H2O)]^+\}}$ (see box).
In this chapter we shall use $\ce{H^+(aq)}$ ...
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Estimation methods for temperature evolution of a high $\Delta H_{mix}$ dilution ($\ce{KOH}$ in water)
Question up front: Can temperature evolution in solutions be short-hand-estimated by simple state based calculations - with reasonable expectations of precision? (+/- 10° C)
I am trying to calculate ...
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Solubility of hydrogen
I'm interested in bacterial fermentation which produces molecular hydrogen as an end product. If bacteria produce molecular hydrogen in solution under anaerobic conditions, does this remain dissolved ...
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What does it mean for a substance to be "sparingly soluble"?
I have trouble understanding what solubility means. Merriam-Webster defines it as follows:
1 the quality or state of being soluble
2 the amount of a substance that will dissolve in a given amount of ...
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1
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2
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What is the hydrated diameter of a lithium ion？
When salts dissolve in water, the anions, cations, and strongly polar water molecules undergo hydration reactions, resulting in the formation of hydrated ions with a specific number of coordinated ...
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Why does balancing the reduction of dichromate(VI) to chromium(III) require four water molecules among the products?
Problem
Balance the following chemical equation using oxidation numbers:
$$\ce{Cr2O7^2–(aq) + HNO2(aq) –> Cr^3+(aq) + NO3–(aq)}$$
Solution (in Swedish)
$$\ce{\overset{+VI}{Cr}_2O7^2–(aq) + H\...
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1
answer
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Soluble Ion separation [closed]
Is it possible to separate ions dissolved in solution? I know that the charges have to be balanced, so thinking that maybe it is possible to artificially give that charge? Take for example, sodium ...
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0
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Increasing energy density for flow batteries with water based electrolyte?
Given a flow battery with a water based electrolyte, would it be possible to increase the energy density of battery by precipitating the redox active species from the anolyte and catholyte solutions? ...
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3
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Aqueous state on CO2 and O2 in the Photosynthesis Chemical Equation
While reading through a book I came across the equation for photosynthesis:
$$ \ce{6CO2(aq) + 12H2O(l) -> C6H12O6(aq) + 6O2(aq) + 6H2O(l)}\tag{1} $$ in the presence of sunlight + chlorophyll.
For ...
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1
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0
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Freezing of a beverage
I am trying to generally describe the process of freezing beer and how the different ingredients influence the freezing process. My general approach right now is to observe a beer as 90% water and 10% ...
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1
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Mass of gaseous ammonia required to prepare ammonia solution of a given pH
How many grams of gaseous ammonia do you need to make $\pu{200 mL}$ aqueous ammonia solution with $\mathrm{pH} = 11.34?$
As the mole ratio is the same for $\ce{H+}$ and $\ce{NH3},$
$$\ce{NH3 + H+ -&...
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1
vote
0
answers
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visualization problem of dilution of enthalpy $\Delta_{dil} H$ data with different initial concentrations
description
I have a question about the $m_f$ vs. $\Delta_{\text{dil}} H$ plot in some experimental studies.
For example, the dilution-of-enthalpy data at 300 °C with two initial concetration ($m_i$) ...
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1
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Is it possible to make acids and bases in amphiprotic solvents other than water [closed]
In such solvents, could there be chemicals which could donate/accept protons, and if so could their solutions display acidic/basic properties?
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2
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2
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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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0
answers
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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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1
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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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1
answer
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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 ...
0
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2
answers
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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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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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4
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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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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 ...
2
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1
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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 ...
0
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1
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262
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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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1
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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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4
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1
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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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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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4
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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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0
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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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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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2
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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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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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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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1
answer
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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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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 ...
2
votes
1
answer
103
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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 &...
2
votes
1
answer
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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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