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 do you find the %mass and/or concentration of Fe in green vegetables? [on hold]

How do you find the %mass and/or concentration of Fe in green vegetables such as silverbeet, spinach and parsley using colorimetry and titration?
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Determining the composition of basic copper sulfate by titrimetry

A colleague shared an undergraduate level classical gravimetry/titrimetry experiment on determining the stoichiometry of basic copper sulfate. I am looking for a reference for this type of experiment. ...
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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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44 views

How a titration curve is affected when a poorly soluble salt is formed?

Suppose that I have $\pu{100 mL}$ solution of strong acid, $\ce{HA}$, at $\pu{0.10 mol L^{-1}}$. This solution is titrated with a strong base solution, $\ce{BOH}$, at $\pu{0.10 mol L^{-1}}$. Suppose ...
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How to prevent creation of piranha solution when conducting hydrogen peroxide titration?

I'm testing the activity of horseradish peroxidase (HRP) under different conditions by measuring the change in concentration of hydrogen peroxide substrate after a given amount of time. To stop the ...
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202 views

How to derive the conductivity titration curve which accounts for salt formation

I derived an equation that gave me the volume of base required to get a certain $\mathrm{pH}$: In a titration between a weak acid $\ce{HA}$ and weak base $\ce{B}$ (adding base into acid solution) the ...
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35 views

Using concentrated sulfuric or nitric acid during titration of permanganate with oxalic acid

During titration of $\ce{KMnO4}$ with $\ce{H2C2O4}$, can we use concentrated $\ce{H2SO4}$ or $\ce{HNO3}$ instead of bench sulfuric acid?
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64 views

Titration of barium(II) hydroxide by hydrochloric acid

$\pu{25 ml}$ of $\pu{0.024 M}$ $\ce{HCl}$ is titrated into a volumetric flask which initially contains $\pu{45 ml}$ of $\pu{0.034 M}$ $\ce{Ba(OH)2}$. Calculate the $\mathrm{pH}$. This is how I ...
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1answer
32 views

Evaluate indicator choice (phenolphthalein)

A student wishes to find the concentration of a $\pu{50 mL}$ solution of acetic acid $(K_\mathrm{a} = \pu{1.8e-5}).$ He performs a titration using a solution of $\pu{0.2 M}$ sodium hydroxide. The ...
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Why is the titratable acidity of my wine going down as it ages and oxidises?

I am currently studying chemistry in grade 12 studies and I have come across a halt in my investigation. The experiment was to see how the increase in ethanol would lead to a more acidic wine, ...
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43 views

Titration of aspirin

I have performed an experiment to test how temperature affects how fast aspirin dissolves by titrating solutions at various time intervals. According to this website, aspirin reacts with water as such:...
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35 views

Redox titration or iron(II)

The concentration of $\ce{Fe^2+(aq)}$ can be determined by a redox titration using A. $\ce{KBr}$ B. $\ce{SnCl2}$ C. $\ce{KMnO4}$ (basic) D. $\ce{KBrO3}$ (acidic) Can anyone please ...
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108 views

Calculating pH when weak base is added to an strong acid

$\ce{NH3}$ solution of $\pu{0.1 mol dm-3}$ is being added to a $\pu{25.0 cm3}$ of $\pu{0.1 mol dm-3}$ $\ce{HCl}$ solution. Calculate the pH of the solution when volume of added $\ce{NH3}$ solution is $...
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42 views

Neutralisation Reaction Confusion

What will happen when $\pu{1 mol}$ of $\ce{H2SO4}$ reacts with $\pu{1 mol}$ of $\ce{NaOH}$? Will $\pu{1 mol}$ each of $\ce{NaHSO4}$ and water be formed? Or will $\pu{0.5 mol}$ of $\ce{H2SO4}$ will ...
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174 views

How to calculate the equivalent mass of Na2S2O3? [closed]

Let us consider the following reaction $$\ce{I2 + 2 Na2S2O3 -> 2 NaI + Na2S4O6}$$ Now, in order to calculate the equivalent mass of $\ce{Na2S2O3}$, first I need to calculate it's $n$-factor which ...
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51 views

Finding molarity of hyposulfite solution used in titration

$\pu{0.1 g}$ of $\ce{KIO3}$ is treated with excess $\ce{KI}$ solution. The liberated iodine required $\pu{44 ml}$ of $x$ molar hypo solution. Calculate the value of $x$. I have used the equivalent ...
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207 views

How to calculate the equivalent weight of KMnO4?

Let us consider the following reaction $$\ce{2 KMnO4 + 16 HCl → 2 KCl + 2 MnCl2 + 8 H2O + 5 Cl2}$$ Now, in order to calculate the equivalent mass of $\ce{KMnO4}$, first I need to calculate it's $n$-...
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1answer
29 views

pKa and equivalence point [closed]

I was doing a titration and using $\ce{NaOH}$ as the titrant. The analyte was a weak acid with a $\mathrm{p}K_\mathrm{a}$ of 4.90. Today I want to use another acid with a $\mathrm{p}K_\mathrm{a}$ of 4....
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72 views

Calculating the ph of an unknown solution by measuring the precipitate [closed]

You have an unknown metal hydroxide, but no meters or indicators. You have lead (II) nitrate, which is soluble in it, and lead (II) hydroxide that is insoluble in it. You take one liter of the unknown ...
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39 views

Calculating pH of weak base and strong acid: Why is K(a) not required?

Question: 35mL of 1.5M $\ce{HCN}$, a weak acid(K(a)= $6.2*10^{-10}$) is mixed with 25mL of 2.5M $\ce{KOH}$. Calculate the pH of final solution. The solution given in my textbook is as follows:- $\ce{...
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34 views

Could this solution be resolved by titration?

I have a mixture of $\ce{NH_4NO_3}$ and $\ce{NH_3}$ at $\ce{pH}$ of about 13. It is possible to determine the concentration of both on them by acid-base titration? I was told it's possible, and that ...
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39 views

pKa value of an indicator

Can we deduce the actual value of $\mathrm{p}K_\mathrm{a}$ of an indicator if the $\mathrm{pH}$ range has been given? I know that $\mathrm{pH}$ range is physically the range of values over which an ...
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55 views

pH After Titration

50mL $\ce{SO2}$ titrated with 0.1M of $\ce{KBrO4}$ with reaction: $$\ce{KBrO4 + 4SO2 + H2O -> 4H2SO4 + KBr}$$ The equivalent point is reached when the volume of $\ce{KBrO4}$ is used as much 50mL. ...
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Can sodium carbonate-sodium bicarbonate buffer be used for EDTA titration of calcium?

I am planning to measure general/total hardness (calcium and magnesium) of aquarium water using EDTA titration with Eriochrome Black T indicator. From what I understand, the unknown solution must be ...
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33 views

Diluting a sample of weak base before titration. What happens to equivalence point pH of diluted vs undiluted?

A student titrated a 10.00 mL of 0.20 M methylamine ($\ce{CH3NH2}$) and determined that 10.00 mL of $\ce{HCl}$ was needed to reach the equivalence point. If you diluted your original sample of ...
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64 views

Why do we assume 100% ionization for acetic acid (a weak acid)? [closed]

This is about a titration. The base titrant used is sodium hydroxide.
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Predicting Glycine-HCl's multiple equivalence points

I have currently completed a titration curve for glycine-HCl (2omL @ 0.1M, therefore 2.0mmol) where I have the known pH at each interval of added NaOH (adding 4mL each interval of 1.0M then measure pH)...
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37 views

Reference Books on Electrolysis and Chemical Titration process [closed]

I'm in a General Chemistry course in college. We have laboratory, and then we are supposed to make a report on what we did, etc. I'm not entirely sure what the last laboratory was about, but it was ...
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How can a titration help me figure out the effect of rosmarinic acid on amylase activity?

So with my limited knowledge of rosmarinic acid, I am aware that it is an non-competitive inhibitor and can inhibit the enzyme, amylase. When starch is added to a solution of already mixed rosmarinic ...
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127 views

Percent Dissociated from Titration Curve

Question 818 references the titration curve. Answer is A because $\ce{H+}$ conc $= 10^{-4}$. This is conc of dissociated acid. The conc of the undissociated acid is the original concentration minus ...
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99 views

How to standardise NaOH? [closed]

My aim is to "To determine the concentration of citric acid in lemon juice using titration technique." and as following i need to standardise the NaOH in order to titrate it with validity. Is there a ...
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1answer
100 views

Effects of Ka on the Half-Equivalence Point

I'm new to studying chemistry at a university level and am currently reviewing acid-base titrations. I am wondering about the relationship between your ionization constant for a weak acid ($K_\mathrm{...
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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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Polyprotic Acid Titrations

Titrating a mixture of strong and weak acids will yield endpoints such that the volume of base required to reach each endpoint will be different for each acid, e.g. in a mixture of HCl and CH3COOH, ...
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70 views

Why would CuSO4-EDTA drops be used in Pb titrations?

We use CuSO4-EDTA drops (4) when preparing our lead titration samples for final titration by EDTA. What mechanism would there be for adding this to a titration? What benefit does it produce on Pb ...
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How do I make a solution of spinach to titrate with pottasium permanganate? [closed]

My teacher said something about straining it but I didnt quite get it
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What are some ways to measure sugar concentration of fruits? [closed]

I've tried to do titrations using the quantitative Benedict's Solution and it was difficult to use as I do not have a way of keeping a constant temperature. I am currently using a Polarimeter to find ...
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Should the tip of the burette of an automatic titrator be immersed in the analyte?

In all the tutorials I found online, the tip of the burette (containing the titrant - NaOH) was immersed into the analyte solution. My question is: shouldn't the tip be out of the solution? Isn't ...
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Looking for experimental data for titration curves

I am looking for real, open source and free experimental dataset (not image, scan of table) of acid/base titration curves: pH versus titrant volume for many combination (strong/weak acid/base, ...
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What is the benefit of using a pH indicator reagent over pH strips or a meter?

I've recently started getting into chemistry a bit as a hobby. Nothing serious, just amateur level stuff mostly, primarily just to educate myself. Whenever I need to determine the pH level of a ...
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292 views

Is the titration of sodium carbonate with hydrochloric acid temperature dependent?

I am a chemistry teacher in a Cambridge school. In one of the titrations of sodium carbonate with HCl, there was one question asked: On heating the sodium carbonate solution before doing the ...
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131 views

Regarding Analysis for CO2 Absorption in NaOH

Background Lab experiment, packed glass column (random packing of metal/ceramic material), countercurrent gas absorption, flowrates measured using rotameters, $rt \approx 27^\circ C$. 2 N NaOH flows ...
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Does diluting the titration flask change the molarity

I was solving the following problem on a test and I thought the answer was A, but the answer is actually D. Below is the problem and my reasoning: Answer choice B is clearly incorrect because the ...
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Acid value of linseed oil

For this we weigh $\pu{1.015 g}$ of linseed oil which is dissolved in alcohol. 3 drops of phenolphthalein (pH indicator) are added and a solution of potassium hydroxide of concentration $C = \pu{9.5e-...
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Oxidation of sodium thiosulfate by iodine

When $\ce{Na2S2O3}$ reacts with $\ce{I2}$, it undergoes a redox reaction as $$\ce{2 Na2S2O3 + I2 -> Na2S4O6 + 2 NaI}$$ Sulfur is being oxidized from a $+2$ state to a $+2.5$ state. Why isn't it ...
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Eriochrome Black T titration - Concentration of Indicator and endpoint

While not as frustrating an indicator as murexide, Eriochrome Black T's wine red to blue transformations provide significant challenges. The change from "fully wine red" to "fully blue with no trace ...
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Iodometric Titration - Iodine Crystal formation

During an iodometric titration iodide is oxidised to iodine by an oxidiser, and then titrated using standardised sodium thiosulfate. I have had no problems using iodate as the oxidiser, however, using ...
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248 views

How to detect equivalence points? [duplicate]

How do we detect equivalence point from a titration of an acid with a basic titrant from thу titration curve ($\mathrm{pH}$ vs. Volume of titrant added)? Can we predict an equivalence point just by ...
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Is volume of strong base used with strong acid same as volume used with weak acid?

At the equivalence point, why do we take volume of strong base used for titration of strong acid the same as the volume used for titration of weak acid? Shouldn't there be a difference? For example, ...
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Titration curves

If I were to model the titration of $30 \ \text{cm}^{3}$ of $ 3 \ \text{mol dm}^{-3}$ $\ce{CH3COOH_{(aq)}}$ with $3 \ \text{mol dm}^{-3}$ $\ce{NaOH_{(aq)}} $ , what would the equation look like (...