All Questions
Tagged with aqueous-solution acid-base
255
questions
-4
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1
answer
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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 ...
- 191
3
votes
1
answer
180
views
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:
...
- 167
0
votes
2
answers
194
views
What might cause overestimated measured pH value of sodium hydroxide solution pumped with carbon dioxide?
I tried an experiment at home where I had a $\ce{CO2}$ tank pumping $\ce{CO2}$ into a solution of $\pu{28 g}$ sodium hydroxide in $\pu{200 ml}$ water. The initial $\mathrm{pH}$ was $11.24.$
I expected ...
- 59
1
vote
1
answer
480
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Acid dissociation constant calculated from the ionization percentage
The question goes like this:
An acid (HX) is 25% dissociated in water. If the equilibrium concentration of HX is $\pu{0.30 M}$, calculate the value of $K_\mathrm{a}$.
So I tried as follows:
if I ...
1
vote
0
answers
87
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How do two species from the same buffer system have different pKa values? [closed]
$$
\begin{array}{lr}
\hline
\text{Reagent}~(\pu{0.1 M}~\text{solutions}) & \mathrm{p}K_\mathrm{a} \\
\hline
\text{Ammonia} & 9.25 \\
\text{Acetic acid} & 4.75 \\
\text{Ammonium chloride} &...
- 19
3
votes
1
answer
1k
views
Why is hydrogen peroxide acidic in aqueous solution?
This seemed like a trivial question to me... until I began to think about it.
The "usual" criteria for greater acidity are larger sizes of the atom attached to the acidic proton within the ...
- 725
0
votes
1
answer
119
views
How exactly does a buffer made up of a weak acid and its conjugate base work upon addition of hydroxide ions? [duplicate]
Consider a buffer solution containing a weak acid and its conjugate base ($c_\mathrm{total} = \pu{0.1 mol L-1}$):
$$\ce{HA <=> H^+ + A^-}$$
When $\ce{H+}$ ions are added (from a strong acid), ...
- 551
1
vote
1
answer
366
views
Calculating pH of aqueous ammonium hydrogen sulfide solution
I was doing the following question yesterday:
Calculate the pH of a $\pu{0.1 M}$ solution of $\ce{NH4HS}$, given $\mathrm{p}K_\mathrm{b}$ of $\ce{NH3}$ is $4.74$, and $\mathrm{p}K_\mathrm{a1}$ and $\...
- 1,411
23
votes
3
answers
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Is "Sulfuric acid... makes a poor electrolyte... very little of it will dissociate into ions" really true? What does that actually mean?
While researching chromate conversion coating for edits to this answer in Space Exploration SE, I came upon the following passage in Corrosion Resistance of Stainless Steel to Sulfuric Acid
Sulfuric ...
- 5,900
-1
votes
1
answer
199
views
How are acids in aqueous solution able to react again after reacting with water?
I hope to clear up some confusion I have about acid-base reactions in aqueous solution.
Based on the Bronsted-Lowry definition of acids, I know acids donate protons. In water, a strong acid should ...
3
votes
1
answer
2k
views
How to determine the equivalents of OH- in a titration curve
How does one go about determining the equivalents of $\ce{OH-}$ needed for the titration of a weak acid. For example here is the titration curve for Aspartate:
Why is the equivalents for $\mathrm{p}...
- 67
-1
votes
1
answer
1k
views
Why does acetate ion react with water? [closed]
When NaCl is added to water, it dissociates into $\rm{Na^+}$ and $\rm{Cl^-}$. The newly formed $\rm{Na^+}$ and $\rm{Cl^-}$ do not react with water.
When $\rm{CH_3COONa}$ (sodium acetate) is added to ...
- 171
5
votes
1
answer
138
views
What is the dissociation percentage of a polybasic organic acid at a certain pH?
For my Master's Thesis I am working with the dicarboxylic acid muconic acid $(\ce{H2MA},$ $\mathrm{p}K_\mathrm{a1} = 2.9,$ $\mathrm{p}K_\mathrm{a2} = 4.0).$ It thus dissociates into $\ce{HMA-}$ and $\...
- 59
6
votes
1
answer
2k
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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 ...
- 1,134
6
votes
1
answer
2k
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pH of an aqueous solution with acetic acid and sodium acetate
An aqueous solution of $\pu{1L}$ contains $\pu{0.2 mol}$ of acetic acid and $\pu{0.2 mol}$ of sodium acetate ($K_\mathrm{a} = 1.8 \times 10^{-5}$). Compute the $\mathrm{pH}$ .
I'm trying to help my ...
- 171