Questions tagged [aqueous-solution]
For questions relating to compounds dissolved in water and resulting reactions and acid-base equilibria.
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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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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 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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Why doesn't the boiling point of an aqueous solution depend on intermolecular attraction?
I understand that boiling point is a colligative property for aqueous solutions, and that it empirically depends on the mole fraction of the solute, rather than the identity of the solute. I ...
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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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Is it possible to achieve a level of "truly zero" concentration? [duplicate]
If we take some aqueous solution and dilute it further and further, will the concentration of the solution ever get to zero? I would say no, simply because total dilution implies that all the ...
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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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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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Why does Mg react vigorously in NaCl solution and less so in water?
When you put $\ce{Mg}$ into water a few $\ce{H2}$ bubbles appear. But when you put $\ce{Mg}$ into a $\ce{NaCl}$ solution there is a vigorous release of $\ce{H2}$, why is this and what reactions are ...
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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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Why are synthetic pH indicators used over natural indicators?
Synthetic indicators seem to be exclusively used when determining the pH of a substance with an indicator (with the exception of that school experiment where you boil cabbage to demonstrate natural pH ...
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Should 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. In many places, it is refer to as bromine solution.
But it is observed that ...
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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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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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Do azeotropic mixtures evaporate proportionally?
Do azeotropes evaporate, without boiling, in proportionate amounts, or does this property describe their behaviour only at boiling point?
Concretely, if 91% isopropyl alcohol/water (by volume, i.e. an ...
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