Titration意思
Titration is a laboratory process used in chemistry to determine the concentration of an unknown solution by reacting it with a solution of known concentration until the reaction reaches a certain point, known as the endpoint. The endpoint is typically indicated by a color change, a change in pH, or the formation of a precipitate.
There are several types of titrations, including acid-base titrations, redox titrations, complexometric titrations, and precipitation titrations. Each type of titration is used to determine the concentration of a specific type of substance, such as an acid, a base, a reducing agent, an oxidizing agent, or a metal ion.
Acid-base titrations are some of the most common types of titrations and are used to determine the concentration of an acid or a base. In an acid-base titration, the endpoint is typically indicated by the color change of an indicator, which is a substance that changes color at a certain pH.
Redox titrations are used to determine the concentration of a reducing agent or an oxidizing agent. In a redox titration, the endpoint is typically indicated by the disappearance of a color, the appearance of a color, or a change in the electrical conductivity of the solution.
Complexometric titrations are used to determine the concentration of a metal ion. In a complexometric titration, the endpoint is typically indicated by a color change, and the titration is usually carried out in an ammonia buffer solution to maintain the correct pH for the formation of the complex ion.
Precipitation titrations are used to determine the concentration of a substance that forms a precipitate. In a precipitation titration, the endpoint is typically indicated by the formation of a precipitate, and the titration is usually carried out with a solution that is in excess, so that all of the substance being analyzed is converted into a precipitate.