Pyridine is a heterocyclic molecule that exists as a colorless to yellow liquid with the chemical formula C5H5N.

It is a basic, heterocyclic organic molecule. It is also known as azine or pyridine. The structure is similar to benzene, but one of the methine groups has been substituted by a nitrogen atom. It has a terrible, rotten, fishy scent. Pyridine can be produced from ammonia, formaldehyde, acetaldehyde, or crude coal tar.

It is slightly basic and miscible with water. It is very combustible and dangerous if inhaled or swallowed. Some pyridine-related symptoms include nausea, asthmatic breathing, vomiting, headache, laryngitis, and coughing. It is commonly utilized as a precursor to agrochemicals and drugs. It also serves as a useful reagent and organic solvent.


Properties of Pyridine – C5H5N

Pyridine and its simple derivatives are relatively stable and unreactive liquids with strong, unpleasant permeating odors. Pyridine is the hydrogen derivative of this ring; it is benzene with a nitrogen atom replacing one of the CH- or methine groups. Pyridine’s structure is completely similar to that of benzene, with the CH replaced by N.


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


C5H5N Uses (Pyridine)


  • It is a vital raw element in the chemical industry.
  • It serves as an antibacterial in dental care products.
  • It is utilized as a solvent that is appropriate for dehalogenation.
  • It is used in medicines.
  • It is utilized in antifreeze mixtures as a denaturant.
  • It functions as a sulfonating agent.
  • It functions as a reducing agent.
  • It is utilized in dyes and paintings.
  • It serves as a disinfectant.
  • In coordination chemistry, it functions as a ligand.


Pyridine FAQs


Question – Is pyridine an aromatic compound?

Yes, pyridine is an aromatic chemical.


Question: Is pyridine a good nucleophile?

No, pyridine is not an effective nucleophile. The lone pair of nitrogen is partially delocalized around the ring. Then pyridine isn’t a strong base. Hence, pyridine is a weak nucleophile.


Que: Pyridine is more basic than pyrrole. Why?

Ans: Pyridine is more fundamental than pyrrole because the lone pairs of electrons on N are different. As a result, an H+ ion or a Lewis acid can be easily transferred to the pyridine N atom’s lone pair of electrons. Pyridine is also a more effective base than pyrrole.


Question: How is pyridine made?

Pyridine is a chemical product formed by the reaction of acetaldehyde, ammonia, and formaldehyde with a catalyst at temperatures ranging from 250 to 500 degrees Celsius. It is used in medicines, solvents, and dyes.


Question – How many resonant structures does pyridine have?

Ans: Pyridine contains five resonance structures. The five resonance structures containing positively charged carbons demonstrate this phenomenon. As a result, electrophilic substitution reaction rates in pyridine are much lower than in benzene.