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.

Filter by
Sorted by
Tagged with
-1
votes
1answer
663 views

Redox Titration in investigating change of Iron in Avocado [closed]

I'm trying to investigate the change in iron in an avocado as it ripens. I'm planning on using redox titration but still a bit unsure of how to carry out the investigation (method). Do you have any ...
1
vote
1answer
366 views

Application of Nernst Equation in Potentiometric titration of Fe2+ with Ce4+

It is well Known that to find $E_{cell}$ during titration of $Fe^{2+}$ with $Ce^{4+}$ we consider 3 domains: Before Equivalance point , $E_+ = E_{Fe^{3+}/Fe^{2+}}^o+\frac{RT}{nF}log\frac{[Fe^{3+}]}{...
6
votes
1answer
5k views

Buffer formation in weak acid/strong base titration?

I'm a little confused about what happens when you titrate a weak acid or base. For example, let's say that you are trying to titrate a weak acid. Based on this question, it seems like the weak acid ...
1
vote
1answer
154 views

Why is a titration necessary? Why can't we just compare the moles of the acid and base?

For the following question: $\mathrm{1g}$ of $\ce{Mg(OH)2}$ is completely dissolved in $\mathrm{25}$ mL of $\mathrm{0.5}$ M $\ce{HCl}$. This solution is then titrated with $\mathrm{0.1}$ M $\ce{NaOH}...
7
votes
1answer
352 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 ...
1
vote
0answers
31 views

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. ...
9
votes
2answers
2k views

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 ...
1
vote
1answer
58 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 ...
6
votes
2answers
2k views

How to calculate the concentration of conjugate acid from given pH and pKa values?

Preface: Buffer solution (acid-base buffer). I am provided with a weak base, which I will designate B. $\mathrm{p}K_\mathrm{a}$ for $\ce{B}$'s conjugate acid, which I will designate $\ce{BH}$, is $8.1$...
4
votes
2answers
2k views

Error propagation Titration

I hope I am right in this section. I am unsure with error propagation. When calculation the error in a titration, many errors has to be taken into account: Error in Glassware/ Error in Balance/ ...
0
votes
0answers
55 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?
1
vote
1answer
93 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 ...
2
votes
1answer
57 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 ...
2
votes
0answers
32 views

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, ...
0
votes
1answer
1k 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:...
0
votes
1answer
78 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 help me on this ...
1
vote
1answer
472 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 $...
2
votes
4answers
141k views

How come water would not affect the results of a titration?

We were told to rinse the buret with the base so that the concentration won't be messed up, but when it comes to the flask that is going to hold the acid, there is no need to rinse, because it would ...
2
votes
1answer
47 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 ...
-1
votes
1answer
1k 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 ...
0
votes
1answer
4k 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 $n$-...
1
vote
1answer
47 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....
1
vote
1answer
360 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 ...
1
vote
1answer
50 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{...
1
vote
1answer
42 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 ...
0
votes
1answer
369 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 ...
2
votes
0answers
542 views

How to calculate the composition of a mixture of iron oxides containing inert impurities with titration data?

An $\pu{8 g}$ sample of $\ce{Fe3O4}$ and $\ce{Fe2O3}$ containing some inert impurity was treated with excess of aqueous $\ce{KI}$ in acidic medium, which converted all iron to $\ce{Fe^2+}$. The ...
1
vote
1answer
176 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 ...
4
votes
0answers
548 views

Cobalt Oxalate / Potassium Permanganate Titration

My class just did a lab today where we mixed cobalt oxalate with $40~\mathrm{mL}$ of $\ce{H2SO4}$ and then titrated it with $\ce{KMnO4}$ (potassium permanganate). I need the mole ratio of cobalt ...
0
votes
1answer
107 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.
0
votes
1answer
352 views

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 ...
2
votes
2answers
2k views

What's happening at the beginning of a weak acid titration?

At the beginning of a Weak Acid/Strong Base titration curve there is a sharp decrease in $[\ce{H+}]$ and a sharp increase in pH before the ratio between the weak acid and it's conjugate base becomes ...
0
votes
1answer
53 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 ...
1
vote
0answers
29 views

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 ...
2
votes
1answer
142 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 ...
8
votes
3answers
41k views

Calculating Buffer Capacity

I completed a titration of Ammonium Acetate buffer solution and to it I added $\pu{2M}$ Hydrochloric Acid. I measured the initial $\ce{pH}$ of the buffer solution before any acid was added and I ...
0
votes
1answer
311 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{...
0
votes
1answer
397 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 ...
-1
votes
1answer
99 views

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, ...
3
votes
1answer
314 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 ...
0
votes
1answer
317 views

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
5
votes
2answers
148 views

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 ...
0
votes
0answers
91 views

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, ...
0
votes
0answers
574 views

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 ...
-2
votes
4answers
4k views

Titration of Na2CO3 against HCl

$\pu{25 mL}$ of $\pu{0.125 M}$ $\ce{Na2CO3}$ is titrated with $\pu{0.100 M}$ $\ce{HCl}$. Given that $K_\mathrm{a1} = 4.3\times 10^{-7}$ and $K_\mathrm{a2} = 4.8\times10^{-11}$ for the diprotic acid $\...
0
votes
4answers
962 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 ...
2
votes
1answer
246 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 ...
-2
votes
2answers
848 views

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 ...
1
vote
1answer
89 views

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-...
1
vote
1answer
4k views

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 ...

1 2
3
4 5
9