Pyridine - C5H5N

What is Pyridine?

Pyridine is a colorless to yellow liquid with a chemical formula C5H5N. It is a basic heterocyclic organic compound. It is also known as Azine or Pyridin. The structure is like benzene, with one methine group replaced by a nitrogen atom. It has a sour, putrid, and fish-like odor. Pyridine can be synthesized from ammonia, formaldehyde, and acetaldehyde or it can be made from crude coal tar. It is weakly basic and is miscible with water.  It is highly flammable and when inhaled or ingested it becomes toxic. Some of the symptoms, when exposed to pyridine, are nausea, asthmatic breathing, vomiting, headache, laryngitis, and coughing. It is widely used in the precursor to agrochemicals and pharmaceuticals. Also, it is used as an important reagent and solvent.

Properties of Pyridine – C5H5N

C5H5N Pyridine
Molecular Weight/ Molar Mass 79.1 g/mol
Density 982 kg/m³
Boiling Point 115 °C
Melting Point −41.6 °C

Pyridine structure – C5H5N

Pyridine structure

C5H5N Uses (Pyridine)

  • It is used in the chemical industries as a very important raw material
  • It is used as an antiseptic in dental care products
  • It is used as a solvent which is suitable for dehalogenation
  • It is used in pharmaceuticals
  • It is used for antifreeze mixtures as a denaturant
  • It is used as a sulfonating agent
  • It is used as a reducing agent
  • It is used in dyes and paints
  • It is used as a disinfectant
  • It is used in coordination chemistry as a ligand

Also Read:

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Practise This Question

A mixture of three amines A, B and C is treated with Benzene sulphonyl chloride and filtered.' B' is obtained in the filterate. The mixture containing A and C is treated with KOH so that' A' becomes soluble while 'C' does not. Now A, B and C are