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 I Calculate the Concentration Of Vitamin C? ( It Is Urgent) [closed]

For My Experiment I am testing the vitamin c concentration of vegetables. I blended 50g of spinach and then added water to it until it became 100ml. I then took 20 ml from this solution and poured it ...
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Equivalence point of titration of Sodium carbonate

The pH at the equivalence point of titration of $\ce{Na2CO3}$ solution with $\ce{HCl}$ is around 3.7, as shown in this titration curve: At this point, the following reaction is completed: $$\ce{...
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Will washing a conical flask with deionised water to remove splashes affect the titration result?

When performing a titration, once the acid/base in the burette is slowly released into the conical flask, it may splash onto the sides of the conical flask. It is then advised that we wash the sides ...
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When titrating to find the concentration of a dissolved acid, does the volume of solvent matter?

I am conducting a titration to find the mass of aspirin present in tablets. I will be dissolving the aspirin tablet into a solution of ethanol and distilled water to dissolve it. But, does the volume ...
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Is the Henderson–Hasselbalch equation volume independent?

Looking at this equation $\mathrm{pH} = \mathrm{p}K_\text{a} +\log\frac{[\ce{CB}]}{[\ce{A}]}$ makes me think that it is concentration independent. What I mean is, when we look at $\frac{[\ce{CB}]}{[\...
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How can I mask the Chromium (III) and Chromium (VI) ions in my solution?

I want to conduct a quantitative analysis on my acid etching solution for my Aluminum pre-treatment process. The easiest way for me to conduct my quantitative analysis of Al is through complexometric ...
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Difference in titration curves

In my titration curve for HCl being titrated with NaOH, the initial pH-value was plotted as 2.1 according to a pH-meter. When I found the equivalence point and calculated the concentration of HCl, it ...
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Weak acid titration curve [duplicate]

At the beginning of a weak acid titration curve (when titrated with a strong base), there is a sharp increase of pH before it levels out more due to the buffer solution that will occur. But why is ...
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Acidic KMnO4 oxidizes H2S to S. Why doesn't the oxidation proceed further to sulfur oxide, sulfur dioxide or sulfur trioxide?

I have some idea about the question. I think it has to do with oxidation/reduction potentials but I am not able to find any resource for the exact values or how to make sense of them in this context. ...
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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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pH After titration

$\pu{50mL}$ $\ce{SO2}$ titrated with $\pu{0.1M}$ of $\ce{KBrO4}$ with reaction: $$\ce{KBrO4 + 4SO2 + H2O -> 4H2SO4 + KBr}$$ The equivalent point is reached when the volume of $\ce{KBrO4}$ is ...
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Unusual Titration Curve Explanation

From Costanzo's Physiology book in Acid-Base Physiology chapter, this titration curve of a weak acid ($\ce{HA}$), in the context of discussing buffers is provided: What confused me is that in this ...
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Titration calculations - working out cation [closed]

so I was doing this question and I have some questions about what I did. Firstly am I correct to say that the concordant results = 24.1 cm^3 because there are 2 of these values. From this I then ...
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Does cellulase catalyze the hydrolysis (or break down) of soluble starch?

I’m attempting to perform an Iodometric redox titration to evaluate the vitamin c concentration in a particular solution. These solution have dissolved within them up to 2% cellulase enzyme. In an ...
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does NH4OH lose concentration when it is open? [closed]

I get a lot of variation on NH4OH titration and I am curious if anyone knows if NH4OH at concentration greater than 20% will evaporate the NH3 and decrease in concentration if it is open and at room ...
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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 ...
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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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Why isn't sodium hydrogen phthalate used instead of KHP?

Why is potassium hydrogen phthalate (KHP) ubiquitously synthesized and used as a primary standard, while sodium hydrogen phthalate isn't even available to buy?
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How do you find the pH of lime juice through titration?

I am doing an experiment on the effect of time on the $\mathrm{pH}$ of Lime juice. I was wondering how you would calculate the $\mathrm{pH}$ through titrations using $\pu{1 Molar}$ $\ce{NaOH}$. I have ...
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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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Performing a Redox Titration on a Vitamin C Sample Solution Containing Cellulase enzymes

I was wanting to performing an Iodometric Redox Titration on a Vitamin C sample solution created from allowing diced citrus fruits to sit in a water + cellulase solution. Because vitamin c is water ...
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Do both iodine and potassium iodide turn dark in the presence of starch?

I will do a titration to standardise a solution of sodium thiosulfate with potassium permanganate solution and potassium iodide solution. My book says that when the potassium permanganate solution ...
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Explaining the colour change in the potassium permanganate titration of iron(II) ions [duplicate]

In the redox titration: $$\ce{MnO4- + 8 H+ + 5 Fe^2+ -> Mn^2+ + 4 H2O + 5 Fe^3+}$$ the colour change which occurs is purple to colourless, because of the decreased concentration of permanganate ...
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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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Determining the formula of sodium carbonate hydrate using acid-base titration [closed]

I found this question online at mathsmadeeasy.com: Sodium carbonate exists in hydrated form, $\ce{Na2CO3 · x H2O},$ in the solid state. $\pu{3.5 g}$ of a sodium carbonate sample was dissolved in ...
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Regarding the use of dilute sulphuric acid in this titration

I did a titration today for the first time. A solution of Potassium Permanganate of unknown molarity was titrated against a solution of ammonium iron II sulphate of known molarity. I have to say, ...
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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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Why, in titration, is universal indicator not commonly used?

My teacher said that we always used indicators such as methyl red, methyl orange, litmus, phenolphthalein, etc. rather than universal indicator. I don't understand why, though, would not universal ...
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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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A Spectrophotometric technique to evaluate Vitamin C concentration in Citrus Fruit

Is there a visible spectrophotometric technique that can gage the concentration of vitamin C in solution? I plan on boiling different citrus fruit in water, and taking aliquotes of the boiled solution ...
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Finding the concentration of hydrochloric acid by titration

In a class experiment, $\pu{20 mL}$ of hydrochloric acid was diluted with distilled water to $\pu{500 mL}$. $\pu{20 mL}$ of this diluted solution was added to $\pu{20 mL}$ of $\pu{0.1 M}$ sodium ...
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Conductometric titrations: dilution effect

Since the conductivity of a solution changes linearly with the electrolyte concentration, during a conductometric titration the volume increases with each addition of the titrant aliquot. For this ...
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Which make HCO3- to show two pH values at two scenarios?

According to the below two titrations, Image Reference: https://chem.libretexts.org/Bookshelves/General_Chemistry/Book%3A_Chem1_(Lower)/13%3A_Acid-Base_Equilibria/13.05%3A_Acid%2F%2FBase_Titration If ...
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Protonated forms of EDTA and their constants of formation with metal ions

It is widely known that the fully deprotonated form of EDTA (usually written as Y4-) is the only form that is significantly involved in complexation reactions. From what I have read, this accounts for ...
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How to find the vitamin C content of orange juice?

I'm an IB chemistry SL student doing an IA on the vitamin C concentration of orange juice. We haven't learned about the titration process, so here is what I have done so far: $\ce{5KI + KIO3 + 3H2SO4 ...
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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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Problem encountered during high school unsaturated fats experiment

To get straight to the point, my chemistry experiment was looking at the amount of unsaturated fats in avocado oil with respect to temperature. I did this by testing for the $\ce{C=O}$ bonds using ...
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How Do I Determine The Strength Of Two Ammonia Solutions Using Titration Methods? [closed]

Two housewives disagreed on the strength of an ammonium cleaning agent. Housewife A thought that her brand was more effective than the brand used by housewife B. Plan and design an experiment that ...
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Why rinse flask with distilled water when the flask will be used for storing aliquots of HCl for titration?

In an experiment for standardisation of NaOH with titration, the lab manual instructed students to rinse conical flasks that were supposed to store 1mL aliquots of hydrochloric acid with distilled ...
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Amphoteric amino acid titration

Glycine $(\ce{NH2CH2COOH})$ is an amino acid with two $\mathrm{p}K_a$ values $(\mathrm{p}K_{a,1}=2.0, \ \ce{COOH};\ \mathrm{p}K_{a,2}=10.0, \ \ce{NH2})$. (a) If $\pu{0.01 mol}$ of this amino acid is ...
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Is pK_{In} = pH at equivalence point still true for weak basic organic indicators?

I am reading Ostwald Theory of Titration which says that indicators are organic weak acids or bases. To prove the relation that $\mathrm{p}K_\mathrm{In} = \mathrm{pH}$, the textbook uses the following ...
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How to determine the purity of lactic acid with titration?

$\pu{25 mL}$ of $\pu{0.5 \%(w/v)}$ lactic acid ($\ce{C3H6O3}$, molecular mass $\pu{90.1 g mol-1}$, $\mathrm{p}K_{\mathrm{a}} = 3.86$ was neutralised by $\pu{13.1 mL}$ of $\pu{0.1010 M}$ monobasic base....
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Can the titrant and the unknown material be flipped?

We know the typical experiment of determining the concentration of $\ce{Fe^2+}$, where we titrate $\ce{MnO4^-}$ which has dark purple color and watch the color of the bottle. Can we also determine ...
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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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How come we can't use the equivalence point equation of NV=NV in this problem?

So, the problem is you prepare to standardize a $\ce{Na2S2O3}$ solution. $\pu{32 mL}$ of $\ce{Na2S2O3}$ solution is titrated into $\pu{50 mL}$ of a $\pu{0.01 M} \ \ce{KIO3}$ solution to reach the ...
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Finding the pH among HF and KOH

Okay I ran into this question in homework. A 100.0 ml sample of 0.20M HF is titrated with 0.10 M KOH. Determine the pH of the solution after adding 200 ml of KOH. The Ka of HF is 3.5 x 10-4? Oh yeah ...
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Drying sodium tetraborate for use as a standard

I am currently attempting to purify technical grade sodium tetraborate decahydrate by recrystallization for use as a titration standard. I don't have a requirement for a specific grade or purity. I'm ...
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Confusion about Titration Formula [closed]

When performing a titration of a monoprotic acid and a monoprotic base, water can not be added to the titrant but water can be added to the analyte. To prove this statement to myself, I decided to ...
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Volume calculation perchloric acid 70%

HClO4= 100.5, d HClO4=1.8, (ACO)2O=102, d (ACO)2O=1.1, H2O=18, d H2O=1 A) Preparation of 100 ml perchloric acid 0.1 Molar aqueous solution. below is my answer, but what I'm not sure is that the ...
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What is the difference between Half Equivalence point and Equivalence point?

OKay I learned in class that equivalence point is the time of neutralization, where the # of moles of acids and base present is in equivalence/same amount. Now I was also told that Half equivalence ...

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