Questions tagged [aqueous-solution]
For questions relating to compounds dissolved in water and resulting reactions and acid-base equilibria.
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Can we extract KI from Lugol solution?
I want to extract the $\ce{KI}$ component of the Lugol solution, is there a method to do it? If not, how can I make a $\ce{KI}$ solution?
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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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How does the composition of ice differ from that of water in a partly frozen solution?
Take any solution, then start freezing it at sufficiently low temperature. Soon a small amount of ice forms. I'd like to know how the composition of dissolved salts and gases in the bit of ice differs ...
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Notation "5% solution"
What does 5% aqueous solution of glucose mean? Note that it's just 5% and not 5%w/w. Do we assume it to be w/w?
The question is
If the osmotic pressure of 5% aqueous soultion of glucose is $\pi_1$ ...
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Thermodynamics behind Deliquescence?
The phenomenon of deliquescence wherein a water soluble substance absorbs water from atmosphere and dissolve in it forming a saturated solution, has thermodynamic roots. I have read the fact that the ...
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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 Add Salt to Vinegar to Clean Pennies? [duplicate]
One common cure for dirty pennies is to put them in vinegar and salt. The vinegar should react with the copper oxide on the penny in the following way:
$\ce{2CH3COOH + CuO -> (CH3COO)2Cu + H2O}$
...
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What is the colloidal osmotic pressure?
The oncotic pressure or colloidal osmotic pressure is the osmotic pressure developed due to the presence of colloids in a solution. But since the colloids are not true solution, why should the ...
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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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Would dissolving a salt and letting it sit for 48 hours have an effect on the solution?
If one were to dissolve magnesium citrate (about $100~\mathrm{mg}$) in water (about $70~\mathrm{ml}$) and let the solution sit for 48 hours, would the solution be exactly the same as one dissolved and ...
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Crystallization of solutions and liquids
The process of crystallization of a liquid or any solute occurs when its concentration exceeds the maximum concentration which the solvent can carry or when the temperature drops below the freezing ...
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How to solve this contradiction?
I am getting confused about this the more problems I do on it. My understanding was that only strong acids and strong bases will react to produce water and a salt. Something like this:
Molecular Eq: $\...
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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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Time to effervescent an effervescent tablet
Say I have an effervescent tablet and I put in water. I thought that if I break the tablet in two halves it would dissolve quicker than with the whole table (without breaking), but it actually takes ...
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Why do aqueous solutions always have to be electrically neutral?
I was reviewing some analytical chemistry and stumbled upon a section that explained the imperfection of using a salt bridge.
It said that the using dissimilar ions is a problem because in, for ...
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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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What does m± represent in the equation for mean activity of a salt solution?
I need to find the activity $a_\pm$ for a $\pu{0.0120 M}$ solution of $\ce{Na3PO4}$, and have calculated the activity coefficient, $\gamma_\pm = 0.389$.
I know that $$a_\pm = \frac{m_\pm}{m_0}\gamma_\...
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How can one calculate the pH of a solution?
So, I have 1 litre of acetate buffer, and 0.1 mol of oxonium ions/$\ce{H3O+}$ is added. The task is to calculate the pH of this solution.
What I was thinking:
$$\ce{CH3COOH + H2O <=> CH3COO- + ...
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How might one reduce the concentration of bubbles in their ice, from ice cube trays?
So I have been freezing ice a lot recently, and I will come out and say it, as it turns out it is, albeit unlikely, it is sometimes possible for ice to "explode." I was not so aware of this before, ...
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What commonly availible salts are strong dessicants?
I'm looking into building an absorption chiller as a decidedly non-professional DIY project. For safety reasons and because temps. > 0°C are sufficient, I won't be using ammonia but some saline ...
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Hypochlorous acid mechanism
When hypochlorous acid is dissolved in water, is it the chlorine atom or the oxygen that serves as the anti microbial agent?
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Why is my NaCl solution seemingly saturated, when I followed the recipe for an isotonic solution?
I prepared an isotonic solution of table salt in water following this recipe: 1 leveled coffee spoon of salt in 0,5L of water.
9g/L would be an isotonic solution, a leveled coffee spoon is commonly ...
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What is the exact definition of Salinity?
I am a bit unclear on the definition of salinity. I have always thought of it as simply total dissolved ions.
Wikipedia seems to agree "saltiness or dissolved salt content" but many other sources ...
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Separating NaClO from its aqueous form in bleach
I was wondering, can I separate the $\ce{NaClO}$ from the $\ce{H2O}$ in bleach. The decomposition point for $\ce{NaClO}$ is $374.14\ \mathrm{K}$, so I'm risking decomposing the compound if I do simple ...
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Which species dissociate completely in ionic equations?
I am tasked with writing a molecular equation, an overall ionic equation, and a net ionic equation for the reaction between an aqueous solution of phosphoric acid, $\ce{H3PO4{(aq)}}$ and an aqueous ...
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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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Maintaining a 40% CO₂ aqueous environment?
I wish to grow algae in a 40% $\ce{CO2}$ (water under air with 40% $\ce{CO2}$ content) aqueous environment.
Simple DIY methods are available, but they are generally unreliable (For more info on DIY ...
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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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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 is it called "carbonation"?
Why is it referred to as "carbonation" and we drink "carbonated" beverages when carbonate is $\ce{CO3}$ while $\ce{CO2}$ (carbonite?) is present in carbonation?
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Do dishwashing detergent and stain remover powder/stick have the similar ability to remove collar rings?
For yellow rings on shirts caused by skin grease or sweat:
Some recommended to use an "Oxyclean" stain remover or stain remover stick
for cleaning.
Some recommended to use dishwashing detergent to ...
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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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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 would I calculate the Normality of a 0.00167 molar solution of KIO₃?
I need a 0.01 N solution of $\ce{KIO3}$ to use as a standard in a Winkler titration. The protocol that I am using specifies that this is 0.3567 g L-1, which I have calculated to be 0.00167 M based on ...
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How to calculate the equilibration time of two connected chambers of salt solution, initially at different concentrations?
I am trying to build a system of two connected chambers, one of which is also connected to a cuvette, so I can perform a spectrometry experiment with different concentrations of $\ce{KNO3}$ solution. ...
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Why is water ignored in the ionic equilibrium of HF?
While trying to understand the solution of a problem given in my textbook, I realized I'm having some difficulty with the solution. The problem is as follows:
The ionization constant of $\ce{HF}$ ...
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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 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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How to understand this form of writing the solution: (some salt • n H₂O)?
For example — "high purity chloride salt of Zinc $(\ce{ZnCl2.2H2O})$" or "various concentrations of $\ce{FeCl2.4H2O}$". What does the number before $\ce{H2O}$ mean?
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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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