Nitric Acid (HNO₃)

Nitric Acid is a tough acid with the chemical formula HNO₃. Its theoretical form is colorless, but as it ages, it turns yellow. This yellow color appears due to the breakdown of nitric acid into oxides of nitrogen and water.

It is very corrosive and highly toxic, capable of causing severe skin burns. Nitric acid reacts with hydroxides, metals, and oxides to form nitrate salts. It is also a strong oxidizing agent.

Nitric acid is commonly produced by the catalytic oxidation of ammonia. It is widely used as a laboratory reagent and plays an important role in various industries, especially in the production of explosives and fertilizers.

???? The pH of nitric acid is approximately 3.01.

Structure of Nitric Acid

• A nitric acid molecule contains three oxygen atoms, one nitrogen atom, and one hydrogen atom.

• In HNO₃ molecules:

  • One oxygen atom is double-bonded to the central nitrogen atom.

  • Another oxygen atom is singly bonded to the nitrogen atom and singly bonded to a hydrogen atom.

  • The third oxygen atom has a -1 charge and is singly bonded to the nitrogen atom.

• Since the central nitrogen forms four covalent bonds, it has a +1 charge.

• The net charge on the nitric acid molecule is 0.

• The charges in these molecules can be delocalized due to resonance.

Uses of Nitric Acid

1. Fertilizer Production

   • Ammonium nitrate is produced from nitric acid, which is further used in making fertilizers, plastics, and dyes.

2. Explosives

   • Nitric acid is essential for producing explosives such as TNT (trinitrotoluene).

3. Rocket Propellant

   • Acts as an oxidizer in liquid-fueled rockets.

4. Electrochemistry

   • Used as a doping agent in electrochemical processes.