A report on Titration

A burette and Erlenmeyer flask (conical flask) being used for an acid–base titration.
Analysis of soil samples by titration.
A typical titration curve of a diprotic acid titrated with a strong base. Shown here is oxalic acid titrated with sodium hydroxide. Both equivalence points are visible.
Methyl orange
Phenolphthalein, a commonly used indicator in acid and base titration.
Color of iodometric titration mixture before (left) and after (right) the end point.
An elementary pH meter that can be used to monitor titration reactions.
A titration is demonstrated to secondary school students.

Common laboratory method of quantitative chemical analysis to determine the concentration of an identified analyte (a substance to be analyzed).

- Titration
A burette and Erlenmeyer flask (conical flask) being used for an acid–base titration.

39 related topics with Alpha

Overall
Zinc, a typical metal, reacting with hydrochloric acid, a typical acid

Acid

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Molecule or ion capable of either donating a proton , known as a Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis acid.

Molecule or ion capable of either donating a proton , known as a Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis acid.

Zinc, a typical metal, reacting with hydrochloric acid, a typical acid
Svante Arrhenius
Acetic acid, a weak acid, donates a proton (hydrogen ion, highlighted in green) to water in an equilibrium reaction to give the acetate ion and the hydronium ion. Red: oxygen, black: carbon, white: hydrogen.
Hydrochloric acid (in beaker) reacting with ammonia fumes to produce ammonium chloride (white smoke).
This is an ideal titration curve for alanine, a diprotic amino acid. Point 2 is the first equivalent point where the amount of NaOH added equals the amount of alanine in the original solution.
Carbonated water (H2CO3 aqueous solution) is commonly added to soft drinks to make them effervesce.
Basic structure of an amino acid.
Aspirin (acetylsalicylic acid) is a carboxylic acid

Neutralization is the basis of titration, where a pH indicator shows equivalence point when the equivalent number of moles of a base have been added to an acid.

Test tubes containing solutions of pH 1–10 colored with an indicator

PH

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Scale used to specify the acidity or basicity of an aqueous solution.

Scale used to specify the acidity or basicity of an aqueous solution.

Test tubes containing solutions of pH 1–10 colored with an indicator
Relation between pH and pOH. Red represents the acidic region. Blue represents the basic region.
Nutritional elements availability within soil varies with pH. Light blue color represents the ideal range for most plants.
Lemon juice tastes sour because it contains 5% to 6% citric acid and has a pH of 2.2 (high acidity).

One way to do this, which has been used extensively, is to titrate a solution of known concentration of a strong acid with a solution of known concentration of strong alkaline in the presence of a relatively high concentration of background electrolyte.

Redox titration

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A redox titration is a type of titration based on a redox reaction between the analyte and titrant.

Acetic acid, a weak acid, donates a proton (hydrogen ion, highlighted in green) to water in an equilibrium reaction to give the acetate ion and the hydronium ion. Red: oxygen, black: carbon, white: hydrogen.

Acid dissociation constant

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Quantitative measure of the strength of an acid in solution.

Quantitative measure of the strength of an acid in solution.

Acetic acid, a weak acid, donates a proton (hydrogen ion, highlighted in green) to water in an equilibrium reaction to give the acetate ion and the hydronium ion. Red: oxygen, black: carbon, white: hydrogen.
Variation of the % formation of a monoprotic acid, AH, and its conjugate base, A−, with the difference between the pH and the pKa of the acid.
Phosphoric acid speciation
Dimerization of a carboxylic acid.
pKa of acetic acid in dioxane/water mixtures. Data at 25 °C from Pine et al.
Fumaric acid
Maleic acid
Proton sponge
A calculated titration curve of oxalic acid titrated with a solution of sodium hydroxide
Cysteine

Experimentally, pKa values can be determined by potentiometric (pH) titration, but for values of pKa less than about 2 or more than about 11, spectrophotometric or NMR measurements may be required due to practical difficulties with pH measurements.

pH indicators: a graphic view

PH indicator

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Halochromic chemical compound added in small amounts to a solution so the pH of the solution can be determined visually.

Halochromic chemical compound added in small amounts to a solution so the pH of the solution can be determined visually.

pH indicators: a graphic view
pH measurement with indicator paper
Absorption spectra of bromocresol green at different stages of protonation
Hydrangea in acid soil
Hydrangea in alkaline soil
A gradient of red cabbage extract pH indicator from acidic solution on the left to basic on the right
Purple cauliflower soaked in baking soda (left) and vinegar (right). Anthocyanin acts as an pH indicator.
Turmeric dissolved in water is yellow under acidic and reddish brown under alkaline conditions

For the quantitative analysis of metal cations, the use of complexometric indicators is preferred, whereas the third compound class, the redox indicators, are used in redox titrations (titrations involving one or more redox reactions as the basis of chemical analysis).

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Burette

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Specification (on top of the burette)
Meniscus
Burette with Ring stand
plastic stopcock used in glass volumetric burette

A burette is a graduated glass tube with a tap at one end, for delivering known volumes of a liquid, especially in titrations.

Permanganometry

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One of the techniques used in chemical quantitative analysis.

One of the techniques used in chemical quantitative analysis.

It involves two steps, namely the titration of the analyte with potassium permanganate solution and then the standardization of potassium permanganate solution with standard sodium oxalate solution.

Hardware stores grade sodium hydroxide to be used as a type of drain cleaner.

Sodium hydroxide

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Inorganic compound with the formula NaOH.

Inorganic compound with the formula NaOH.

Hardware stores grade sodium hydroxide to be used as a type of drain cleaner.
Paint stripping with caustic soda
Chemical burns caused by sodium hydroxide solution photographed 44 hours after exposure.
Two industrial fiberglass barrels of caustic-soda

Such acid–base reactions can also be used for titrations.

Equivalence point

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Point at which chemically equivalent quantities of reactants have been mixed.

Point at which chemically equivalent quantities of reactants have been mixed.

The endpoint (related to, but not the same as the equivalence point) refers to the point at which the indicator changes color in a colorimetric titration.

A solution of KMnO4 in water, in a volumetric flask

Potassium permanganate

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Inorganic compound with the chemical formula KMnO4.

Inorganic compound with the chemical formula KMnO4.

A solution of KMnO4 in water, in a volumetric flask
Baeyer's reagent reaction

The value determined is known as the permanganate value. In analytical chemistry, a standardized aqueous solution of KMnO4 is sometimes used as an oxidizing titrant for redox titrations (permanganometry).