Questions tagged [titration]

A laboratory method to determine the concentration of an analyte in solution. The solution volume plays a key role in the analysis.

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How to balanced the equation and how to find the number of moles used in the titrations [closed]

You are required to standardize a dilute solution of sulphuric acid, and undertake the following steps: (i) 4.805 g of solid sodium tetraborate (Na2B4O7) are added to a 250 mL volumetric flask, and ...
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redox titration [closed]

when H2S react with KMnO4- in acidic solution the following reaction can be written 2MnO4- + 5H2S + 6H+ = 2Mn2+ + 5s + 8H2O (balanced) if 0.01 molar of permanganate used to titrate 10 mL of H2S ...
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Using samples in titrations

I've never done an experiment before. So, the methodology provided in this pdf is quite confusing. Link to the pdf: https://www.canterbury.ac.nz/media/documents/science-outreach/vitaminc_iodine.pdf So,...
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Volume required to dilute solution for a pH change

A $\pu{100 mL}$ solution of $\ce{NaOH}$ has a $\mathrm{pH}$ of $13$. What volume of water in $\pu{mL}$ must be added to change the $\mathrm{pH}$ to $11$? My steps: Begin by calculating conc. of $[\...
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Understanding equivalence point [closed]

I read this passage: “It is important to emphasize that, while a strong acid/strong base titration will have its equivalence point had a pH of seven, the equivalence point does not always occur at pH ...
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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}...
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Finding the Ka of a weak acid after addition of a strong base

When 50.00 mL of an unknown 0.2461 M weak acid are titrated with 0.1968 M NaOH, it was found after the addition of exactly 16.00 mL of base that the pH of the solution was 3.79. From this information, ...
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How measured content of Calcium Carbonate in eggshells change with the use of different acids?

I am investigating the calcium content of chicken eggshells. The only literature I can find on this consistently and solely depend on the use of HCl to conduct back titration. I conducted the ...
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How is indigo carmine used in Lowenthal-Permanganate titration as a redox indicator?

In a Lowenthal-Permanganate titration, cider tannins are quantified by titrating the cider with indigo carmine indicator and sulfuric acid against potassium permanganate. Tannins are antioxidants, so ...
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Could the pH in the equivalence point of strong acid and strong base titration be greater than 7? [duplicate]

I have HCl and NaOH titration and in the equivalence point I get pH=8.6, but the pH must be 7 in this kind of titration, then why this happen? Does it possible that I don't take enough points in the ...
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Why does the pH before the equivalence point of a titration depend on the initial concentration only when the acid is strong?

SO, in this picture, two different titration curves are shown: one for a weak acid, one for a strong acid. I'm confused as to why for a strong acid, if you vary the concentration of the acid, (and the ...
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Which method has the highest yield of calcium sulfate?

I'm not sure which of following two methods will give better yields for $\ce{CaSO4}$: A. Add dilute $\ce{HNO3}$ to $\ce{CaCO3}$, followed by dilute $\ce{H2SO4}$; or B. Titrate aqeuous calcium ...
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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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Procedure for measuring EC

Most of the procedures on the internet are of a university research lab level. Is there a simpler method I could use to determine the concentration of EGCG
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How do we calculate N factor and why is it useful in calulations?

I don't understand the concept of N factor at all. Why is it important? I know that it is something dependent upon the oxidation number, for example N factor of Na would be 1 since it has oxidation ...
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Finding the equivalent point of a weak polyprotic acid when reacted with a strong base

I have a graph of a titration of a weak polyprotic acid with a strong base. I graphed $\mathrm {pH}$ versus amount of strong base added. Now since the acid is polyprotic, how do I determine which ...
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Titration of H+ by iodometry

Propose a titration protocol for a hydrochloric acid solution of approximate concentration 0.1M using the solutions and materials available. Solutions: -$V_0$ = 20mL of hydrochloric acid solution of ...
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What are some example of the use of argentometric titration?

Like, we use alkalimetric titration to calculate the real concentration of table vinegar. What about argentometric titration?
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Do acids and bases have the same coefficients if they neutralize one another?

The questions states: Ammonia has the formula $\ce{NH3}$. Household ammonia is a dilute aqueous solution of $\ce{NH3}$. Aqueous ammonia is a base that can neutralize acids. If 18.2 mL of 0.800 M $\ce{...
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Filling a buret tip before an experiment

I have a question that asks if the buret tip is not filled before the experiment what would happen (effect on molarity for acid/base titration). The way I'm thinking about it, it's not like you're ...
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1answer
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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 ...
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How to prove at what pH the color of an indicator will change based on its pKa?

The equivalence point of an acid-base titration can be determined by choosing the appropriate colored indicator. This indicator is a weak acid $\ce{HA}$. The undissociated acid has a different color ...
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How to (numerically) model a phosphoric acid titration curve

I've been learning how to simulate a 1M phosphoric acid titration curve using numerical methods in R. So far has this has been the best curve: Notice how it flattens out (artificially) towards the ...
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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 ...
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Acid titration of sodium acetate in the presence of sodium ethoxide, is it possible?

I have an aqueous solution of ethanol of $30 - 40\text{ V%}$ that contains a few (unknown) $\text{%}$ ethyl acetate (ethyl ethanoate - $\ce{EtOAc}$). I wonder if I can quantitatively determine the $\...
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What are the reactions occurring during the titration of a carbon dioxide contaminated water sample with diluted sodium hydroxide solution?

During estimation of dissolved $\ce{CO2}$ in water, we took a water sample, added few drops of phenolphthalein and titrated it against dil $\ce{NaOH}$. Questions What are the reactions that happen: ...
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Concentration of weak acid neutralized by strong base [closed]

I've got a question that should be simple enough but I must be doing something very wrong. A $\pu{10mL}$ sample of $\ce{H2SO3}$ is neutralized by $\pu{18.6mL}$ of a $\pu{0.10M}$ strong base. Find the ...
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My EDTA titration isn't giving the right titre

I am, as a fun off-syllabus investigation, looking at hard water and how effective the EDTA titration method is, for permanent and temporary hard water. I ran a titration today and had horrific ...
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268 views

Ratio of conjugate bases of a tricarboxylic acid

A tricarboxylic acid $\ce{H3A}$ has three different types of $\text{p}K_\text{a}$ $(\text{p}K_\text{a, 1} =2.0,$ $\text{p}K_\text{a, 2}=5.0,$ $\text{p}K_\text{a, 3}=8.0)$. Identify the ratio of the ...
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How to calculate the concentration of a monoprotic organic acid that was extracted into an ethyl ether layer?

Compound A is a monoprotic organic acid. If $\pu{25.0 mL}$ of a $\pu{0.456 M}$ solution of A in water was extracted with $\pu{25.0 mL}$ of ethyl ether and it was determined experimentally that $\pu{5....
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Titration of weak acid and strong base at low concentrations [duplicate]

Titration continues until one of the reactants (the one in conical flask) turns out to be a limiting agent as far as I know. From the titration of a weak acid and a strong base, I could learn that the ...
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Preparation of phosphate buffer of ph 7.4

Can I make a phosphate buffer of pH 7.4 starting with phosphoric acid and then adding NaOH until the pH reaches 7.4. What are the disadvantages of using this method over sodium phosphates?
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Temperature at which the reaction Oxalic acid + KMnO4 becomes autocatalytic

As described many times, the reaction between oxalic acid and potassium permanganate can be autocatalytic due to the production of Manganese ions. I've read that this only occurs at higher ...
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titrating a weak acid with strong base in the present of buffer

I would like to get a neutral salt solution for a weak acid whose pKa is 3.42. This weak acid is in the form of solution (now is 20% w/w), thus I cannot directly dissolve the powder into the buffer ...
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Is there a certain amount of titrant that is ideal?

For an AP chem lab dealing with determining the amount of citric acid in orange juice by titrating with NaOH, one of the discussion questions goes like this: Choose an amount of beverage to be ...
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What is the difference between the titration of a strong acid with a strong base and that of the titration of a weak acid with a strong base?

Which of the following statements best characterizes the difference between the titration of a strong acid with a strong base and that of the titration of a weak acid with a strong base? A) Both ...
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How to find the concentration of an of ammonia solution by titration with nitric acid?

I am stuck with this question I am doing: To determine the ammonia ($\ce{NH3}$) concentration in a cleaning product, a chemist diluted 20 mL of the product to 500 mL. Of the 500 mL solution, 25 mL ...
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Calculating pH: Weak Acid, Strong Base

This is a question that had me puzzled for quite a while. I feel that information is missing. A weak acid, $\ce{HA}$, $K_\textrm{a} = \pu{1.0E-4 M}$, is titrated with $\ce{NaOH}$. The concentration ...
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Will potassium permanganate react with ferric chloride?

I came across a question : Which of the following compound does not decolourise an acidified solution of $\ce{KMnO4}$? Answer was: After doing a bit of research I found that $\ce{KMnO4}$ oxidises $\...
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Is there a potentiometric method for monitoring salt formation in organic solvent?

I work in a pharmaceutical R+D lab, and currently aim to develop a validatable potentiometric method for determining the optimal amount of acid to add to a basified small organic molecule for ...
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Replacement for Centrifuge in Calcium Content Determination

Basically, I'm performing a lab investigation to determine calcium content in different milk sorts. Since my school didn't have any EDTA, I'm using Sodium Oxalate to form a precipitate with Calcium ...
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Why can indicator pKa be less than the pH at equivalence?

An indicator usually has a pH at equivalence tolerance range around its pKa value that is suitable for titration. However, if the pH at equivalence exceeds the indicator's pKa, wouldn't most of the ...
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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}...
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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 ...
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How is the selective titration testing equation simplified?

When there is $\ce{N^m+}$ and $\ce{M^n+}$ metal ions in a solution with respective m and n charge, $\ce{N^{m+}, M^{n+}}$ reacts with EDTA($\ce{Y}$) as follows: $$\ce{N^m+ + Y^4- <=> NY^{m-4}}$$...
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Determining iron content by titration

The redox reaction is $$\ce{KMnO4-(aq) + 8 H+(aq) + 5 e- -> Mn^2+(aq) + 4 H2O(l)}.$$ Where does $\ce{H+}$ come from in this reaction? What happened to $\ce{K+}$ in potassium permanganate?
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Sodium carbonate titration in presence of phenolphthalein

Why phenolphthalein cannot show the endpoint for the complete titration of Na2CO3 with only phenolphthalein? What's the reason that we consider only half of the moles of sodium carbonate when ...
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Titration curve equation/function

How can I create a graph of a titration curve (acid-base, strong or weak, not something specific), with an equation or a function. In other words, what is the equation that describes such a curve that ...
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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 ...
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EDTA titrations of singly charged cations

It is well known that EDTA can be used for titrations involving complexations of highly charged metal cations, with the most well known being those of the alkali earth metals and transition metals. ...

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