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What is Acid-Base Titration?
A titration is a scientific procedure used to determine the concentration of an unknown substance in a solution. A titration involves adding a measured volume of one solution, called the titrant, to a measured volume of another solution, called the analyte. The titrant is typically a strong acid or base and the analyte is typically a weak acid or base. The titration is complete when the analyte has been completely neutralized by the titrant. The concentration of the unknown substance in the analyte can be determined by measuring the volume of titrant used. Acid Base Titration – Introduction Examples.
What is Acid-Base Titration?
Acid-base titration is a laboratory technique that is used to determine the concentration of an unknown acid or base by measuring the volume of a standard solution of acid or base that is required to neutralize the unknown.
The Endpoint and the Equivalent Point in a Titration
The endpoint of a titration is the point at which the indicator changes color. The equivalent point is the point at which the amount of titrant added equals the amount of analyte in the sample.
Acid-Base Titration Example
In an acid-base titration, a known volume of a strong acid is added to a known volume of a strong base until the two solutions are equivalently acidic or basic. The concentration of the acid or base can then be determined by measuring the volume of the added solution and its concentration.
For this example, we will use a titration to determine the concentration of a sodium hydroxide solution. We will start with a 0.1 M sodium hydroxide solution and add hydrochloric acid until the solution is equivalently acidic. We will use a buret to measure the volume of hydrochloric acid added.
To start, we will add a few drops of hydrochloric acid to the sodium hydroxide solution to create a reaction. We will then use the pH meter to measure the pH of the solution. Continue to add hydrochloric acid to the solution until the pH reaches 2.0. We will then stop adding hydrochloric acid and measure the final volume of the solution.
The concentration of the sodium hydroxide solution can be determined by using the following equation:
[NaOH] = (V * M) / (F * d)Where V is the final volume of the solution, M is the molarity of the sodium hydroxide solution, F is the Faraday constant, and d is the density of the solution.
Key Terms used in Acid-Base Titration
acid
A substance that, when dissolved in water, increases the concentration of hydrogen ions (H+) in the solution. Acids have a sour taste and a pH less than 7.
base
A substance that, when dissolved in water, increases the concentration of hydroxide ions (OH-) in the solution. Bases have a bitter taste and a pH greater than 7.
titrant
The substance that is used to determine the concentration of an unknown acid or base in a solution. In an acid-base titration, the titrant is always a base.
indicator
A substance that changes color in the presence of an acid or a base.
History of Acid-Base Titration
Acid-base titration is a common laboratory technique employed to determine the concentration of an unknown acid or base. The technique involves the addition of a measured volume of a standardized base or acid to a measured volume of the unknown acid or base.
The history of acid-base titration dates back to the early 1800s. In 1817, French chemist Pierre Louis Dulong first described the technique of acid-base titration. Dulong used the technique to determine the concentration of sulfuric acid in a solution.
Acid Base Titration – Introduction Examples.
