29 questions linked to/from How to set up equation for buffer reaction?
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### Am I understanding buffering capacity against strong acid/base correctly?

I just want to make sure I'm understanding buffering capacity correctly. I've been working on this problem: Suppose you have an acetic acid buffer, $\mathrm{p}K_\mathrm{a} = 4.74$, at the ...
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### What are the limitations of the Hendersson-Hasselbalch equation?

Our instructor told us that prior to the equivalence point, the $\mathrm{pH}$ of a solution is dependent on the HH equation. However, when I tried practicing for polyprotic acid titration, I came upon ...
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### Are the best buffers those that are in a 1:1 ratio with its conjugate acid/base?

I wanted to comment this, but I don't have enough reputation, so I just made this a question. I know that buffers and their conjugate base/acid must exist in similar amounts for the buffer to be ...
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### Confusion regarding calculating the pH of a salt of weak acid and weak base

I need to calculate the $\mathrm{pH}$ of a salt of weak acid and weak base in an aqueous solution. Method I used for calculation For a salt of a weak acid and a weak base (assuming complete ...
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### How to find the ionization constant of an unknown weak acid?

A $\pu{0.45 M}$ solution of a weak acid, $\ce{HX}$, has a $\pu{pH}$ of $4.5$. What is the ionization constant, $K_a$, of the acid? $\ce{[HX]}$ is already given as $\pu{0.45 M}$. $\ce{[H+]}$ is given ...
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### What happens when you add a weak acid to a solution buffered at a pH of 8.0?

There are a lot of textbook examples showing what happens to the pH of a buffered solution when you add strong acids and strong bases. Searching for an example calculation where you add weak acids or ...
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### Accurate method to calculate the pH of a salt from a weak acid and weak base

Can someone help me with this? The problem is as follows: Find the $\mathrm{pH}$ of $\pu{1M}$ solution of $\ce{NH4CN}$. Their respective hydrolysis constants are: $K_h = 5.6\times 10^{-10}$ ...
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### Why does a weak base, which is also a salt, dissociate completely in water? [closed]

I'm answering a problem where $\ce{KOH}$ and $\ce{KOAc}$ dissociate nearly as much as each other in separate aqueous solutions at equal concentrations. The problem essentially assumed both completely ...
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### A simple equilibrium problem

Take the following simple equilibrium: $$\ce{CH3COOH + H2O <=> H3O+ + CH3COO-}$$ Ethanoic acid will act as a typical Brønsted-Lowry acid and donate a proton to water, forming a conjugate acid-...
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### Calculate the pH of buffer solution

PROBLEM: A solution was prepared by mixing $\pu{25.00 mL}$ of $\ce{NaOH}$ $\pu{(c = 1mol/L)}$ and $\pu{10.00 mL}$ of acetic acid $\pu{(c = 2.5 mol/L)}$ in water to give $\pu{250 mL}$ of solution. ...
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### When pH > pKa and when pH < pKa and the effectiveness of buffer solutions

I understand that when $\mathrm{pH}= \mathrm{p}K_\mathrm{a}$, the buffer solution will be at its maximum capacity, and there will be equal concentrations of the acid/conjugate acid and the base/...
Using two approximations for the dissociation of a weak acid, we can write $$K_\mathrm{a}= \frac{[\ce{H+(aq)}]^2}{[\ce{HA(aq)}]}$$ One of these two approximations we use is that the concentration of ...