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The process by which an aromatic primary amine is converted to a diazonium compound. The preparation and reactions of diazonium salts were discovered in 1858 and were the basis of the synthetic dye industry and the development of other industrial chemistry in Europe. In diazotization, sodium nitrite is added to a solution of the amine in aqueous acid solution at 0–5°C (32–41°F). Reaction of the amine with nitrous acid gives a nitrosamine. Tautomerization and loss of water lead to the diazonium ion, which is stabilized by delocalization of the positive charge at the ortho and para carbon atoms of the ring, as in the reaction below. See also Amine; Aromatic hydrocarbon; Delocalization. The overall reaction is simple and very general. Substituents of all types—alkyl, halogen, nitro, hydroxyl, sulfonic acid—can be present at any position. Heterocyclic amines such as aminothiazole or aminopyridines can also be diazotized. Aromatic diamines are converted to bis-diazonium compounds. Diazonium salts are generally used and handled in aqueous solution; they are explosive if isolated and dried. The great importance of diazonium compounds in dye technology lies in the coupling reactions that occur with an activated aromatic ring, such as that in phenols or aromatic amines. Coupling, or electrophilic substitution by ArN2+, gives compounds with an arylazo group at the position para or ortho to OH or NH2. Reaction with amines occurs in weak acid solution. With phenols the phenoxide ion is the reactive species, and slightly basic solution is used. See also Chemical equilibrium. The azo dyes obtained in these coupling reactions are one of the important types of synthetic dyes. The color of the dye can be varied widely by choice of diazonium and coupling components. The coupling reaction lends itself to an important method of applying the dye to fabrics. In this process the coupling reagent, such as a naphtholsulfonic acid, is absorbed onto the fiber, and the coupling reaction is then carried out directly on the fiber by passing the fabric through a bath of the diazonium solution. See also Dye.

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Diazotization is which order reaction?

Diazotization reactions are typically considered to be first-order reactions. This means that the rate of the reaction is directly proportional to the concentration of the reactants, specifically the concentration of the diazonium salt.


How many tipes of titration?

There are various types of titration. It is dependent on the conditions used and the reactants and desired products. Some of them are acid-base titration, redox titration, colorimetric titration and thermometric titration.


Why do you use external indicator in diazotization titration?

external indicator is required in diazotization as to observe the end point of the reaction. internal indicators cannot give the endpoint because they may form complexes which may cause hindrance. for example, in the assay of sulfa drugs, iodine-starch paste is used as external indicator, because if we add iodine paste in the conical flask it will react with the reactants and give the blue-black coloration in the beginning of the actions, which will not tell the end point of the reaction. instead, the iodine-starch paste is applied in a paper, and the compound from the burette is added in small quantities into the sulfa drug solution, and after every few milliliters a drop of solution from the conical flask is dropped on the iodine-starch paste, when there is sudden change in colour, the addition from the burette is stopped. and observations are made.


What is over-titration?

Over-titration refers to the process of adding too much titrant during a titration, resulting in an endpoint that goes beyond the equivalence point. This can lead to inaccurate results as the excess titrant can skew the calculations.


What is the scout titration?

The scout titration is a preliminary titration carried out to estimate the approximate endpoint in a titration experiment before performing the actual titration. It helps in determining the approximate volume of titrant required for the main titration to avoid overshooting the endpoint.

Related Questions

What is the purpose of diazotization of cooling the system thoroughly?

The purpose of cooling the system during diazotization is to control the reaction conditions, as diazotization involves the formation of unstable diazonium salts that can decompose at higher temperatures. Cooling helps to stabilize these intermediates, allowing for more efficient and selective reactions. Additionally, lower temperatures can minimize side reactions and improve yields in subsequent steps of the synthesis. Overall, proper cooling is crucial for the success and safety of the diazotization process.


Diazotization is which order reaction?

Diazotization reactions are typically considered to be first-order reactions. This means that the rate of the reaction is directly proportional to the concentration of the reactants, specifically the concentration of the diazonium salt.


How many tipes of titration?

There are various types of titration. It is dependent on the conditions used and the reactants and desired products. Some of them are acid-base titration, redox titration, colorimetric titration and thermometric titration.


Why do you use external indicator in diazotization titration?

external indicator is required in diazotization as to observe the end point of the reaction. internal indicators cannot give the endpoint because they may form complexes which may cause hindrance. for example, in the assay of sulfa drugs, iodine-starch paste is used as external indicator, because if we add iodine paste in the conical flask it will react with the reactants and give the blue-black coloration in the beginning of the actions, which will not tell the end point of the reaction. instead, the iodine-starch paste is applied in a paper, and the compound from the burette is added in small quantities into the sulfa drug solution, and after every few milliliters a drop of solution from the conical flask is dropped on the iodine-starch paste, when there is sudden change in colour, the addition from the burette is stopped. and observations are made.


What is over-titration?

Over-titration refers to the process of adding too much titrant during a titration, resulting in an endpoint that goes beyond the equivalence point. This can lead to inaccurate results as the excess titrant can skew the calculations.


Would you need to use sodium carbonate for the diazotization of m-nitroaniline?

You need to use sodium carbonate when you are attempting to diazotize a poorly soluble acid, such as sulfanilic acid. m-nitroaniline isn't acidic, so adding sodium carbonate would have no effect.


What is the scout titration?

The scout titration is a preliminary titration carried out to estimate the approximate endpoint in a titration experiment before performing the actual titration. It helps in determining the approximate volume of titrant required for the main titration to avoid overshooting the endpoint.


What is the difference between iodometric titration and iodimetric titration?

Iodometric titration involves the titration of iodine with a reducing agent, while iodimetric titration involves the titration of iodide with an oxidizing agent. In iodometric titration, iodine is detected by a starch indicator to determine the end point, while in iodimetric titration, iodide ion concentration is determined by titration with a standard solution of an oxidizing agent.


What is double titration?

Double titration is a titration method used to determine the concentration of a solution by performing two successive titrations. In the first titration, a known concentration of a standard solution is used to titrate the unknown solution. In the second titration, a different standard solution is titrated with the excess volume from the first titration to determine its concentration.


What equipment is used for titration in industry?

titration sensors


What is pilot titration?

Pilot titration is a preliminary test to determine the approximate endpoint of a titration process before conducting the actual titration. It helps in estimating the volume of titrant needed for the main titration, ensuring more accurate and efficient results. The data obtained from a pilot titration can help in planning and executing the main titration with greater precision.


What is Back titration?

A back titration is a form of titraiton in which an excess of standard reagent is added and then the reverse of the titration is carried out.