The correct name for the acid HNO2 is c. nitrous acid.
Nitrous acid is a weak acid and is formed when nitrogen dioxide (NO2) dissolves in water. It is commonly used in the preparation of diazonium salts, which are important in the synthesis of azo dyes. The chemical formula for nitrous acid is HNO2, and it is known for its role in various chemical reactions, including those involving nitrogen compounds.
Here is a brief explanation of the options:
- a. nitrate acid: This is incorrect. Nitrate acid is not a recognized name for any acid.
- b. nitrite acid: This is incorrect. Nitrite acid is not a recognized name for any acid.
- c. nitrous acid: This is correct. HNO2 is known as nitrous acid.
- d. nitric acid: This is incorrect. Nitric acid has the formula HNO3, not HNO2.
- e. hydronitrogen acid: This is incorrect. Hydronitrogen acid is not a recognized name for any acid.