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-2 votes
3 answers
343 views

Why are buffer solutions not neutral

I am very confused about buffer solutions and I have lots of ideas about them which don’t integrate together so I really can’t tell which are correct and which are wrong. That being the case it’s ...
1 vote
0 answers
410 views

Determine the pKa of a diprotic acid by titration (if pKa1 is similar to pKa2)

Determining the acidity constants of a diprotic acid (in my case, tartaric acid) by titration with NaOH and pH-meter is not possible if pKa2 - pKa1 < 2. This is because there are no "pH jumps&...
1 vote
2 answers
629 views

Calculate the pH at the equilibrium point in an acetic acid sodium hydroxide titration

You perform a titration of $\ce{CH3COOH}$ with $\ce{NaOH}$. Let the original concentration of acetic acid be $\pu{0.2 M}$. The volumes of $\ce{CH3COOH}$ and $\ce{NaOH}$ are the same. Then the ...
3 votes
2 answers
2k views

Calculate the titer of a solution

I hope this is the right place to ask. We have this exercise without solution One litre of diluted sodium hydroxide solution (c = 0.15mol/litre) is to be prepared in the laboratory. The titer from ...
-1 votes
1 answer
114 views

Why phenolphthalein is not completely neutralized in basic solutions? [closed]

Phenolphthalein $(\ce{HIn})$ is slightly acidic. Why doesn't it completely break down into $\ce{H+}$ and $\ce{In-}$ and also reacting with all of the $\ce{OH-}$ ion present, unlike $\ce{NaOH}$ and $\...
0 votes
0 answers
55 views

Titration of a weak acid with a strong base

I recently learned that when titrating a strong base like NaOH into a weak acid, like Acetic Acid, a buffer region/zone develops and can be illustrated as follows: CH₃COOH + OH⁻→ CH₃COO⁻ + H₂O I've ...
-2 votes
2 answers
355 views

Acidity and Basicity of titrate and titrant in Acid-Base titration

I want to know that do we always use monoprotic acid and bases in the Acid-Base Titration. And, if the answer is No. Then, I am confused in the definition of Equivalence Point, because I had seen on ...
2 votes
1 answer
8k views

Calculating the pH of the endpoint in a titration of weak acid and strong base

Show that the pH at the endpoint in the titration of $\mathrm{0.100\ mol\ dm^{-3}}$ ethanoic acid with $\mathrm{0.100\ mol\ dm^{-3}}$ sodium hydroxide is 8.72. The dissociation constant Ka of ethanoic ...
1 vote
1 answer
236 views

What is an alternate way of preparing a sodium hydrogen phosphate/sodium dihydrogen phosphate buffer through titrating an acid with a strong base?

So my friend and I are stumped. This is in the context of achieving the sodium hydrogen phosphate/sodium dihydrogen phosphate buffer by titrating the acid with a strong base. My friend says the answer ...
1 vote
0 answers
485 views

Equivalence point pH derivation of a tribasic acid

Considering $\pu{100 mL} \ \pu{0.1 M} \ \ce{H3A}$ and $\pu{0.1 M} \ \ce{NaOH}$ titration curve: I understood the half equivalence points, but couldn't understand the reason why $\mathrm{pH} = \frac{1}...
0 votes
2 answers
787 views

Calculating the pH of a 'buffer' solution?

Question: Determine the $\mathrm{pH}$ of the solution resulting when $\pu{100 cm^3}$ of $\pu{0.50 mol dm-3}$ $\ce{CH2ClCOOH}$ is mixed with $\pu{200 cm^3}$ of $\pu{0.10 mol dm-3}$ $\ce{NaOH}$. The ...
1 vote
2 answers
5k views

Which make HCO3- to show two pH values at two scenarios?

According to the below two titrations, Image Reference If we consider the reactions, at the first reaction (in first figure after adding 1.0), there is $\ce{HCO3-, NaCl,}$ and $\ce{H2O}$ at the first ...
-3 votes
1 answer
5k views

pKa = pH for strong acid — strong base?

I have learnt that for a weak acid — strong base titration, $\mathrm{p}K_\mathrm{a} = \mathrm{pH}$ at the half equivalence point. However, the same conclusion is not drawn when discussing strong acid —...
0 votes
1 answer
783 views

Dissociation constant for Indicators

So I came across a question which asked to calculate the $\mathrm{pH}$ at which an indicator of given $\mathrm{K_{a}}$ would change colour. The solution was given in the following way Since when the ...
0 votes
1 answer
12k views

Find the half equivalence point

How to find the half equivalence point knowing the pH, molarity, titrant added at equivalence point? This a fairly straightforward and simple question, however I have found many different answers to ...

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