Question

Molecular formula of water is ?

• A. \( H_2O \)
• B. \( H_2O_2 \)
• C. \( HO_2 \)
• D. \( H_2O_3 \)

Answer 1

The Correct Option is A

Water is one of the most essential and abundant compounds on Earth. Its molecular formula represents the number and type of atoms in one molecule.

Composition: Water consists of two hydrogen atoms bonded to one oxygen atom.
Formula: H₂O — The subscript "2" indicates two hydrogen atoms, and no subscript after O means one oxygen atom.
Chemical Name: Dihydrogen monoxide (though rarely used in common language).
Molecular Weight: 18.015 g/mol (approximately 18 g/mol).

Why Other Options are Incorrect:
 

• (B) H₂O₂: This is hydrogen peroxide, a different compound used as a disinfectant and bleaching agent.
• (C) HO₂: This is hydroperoxyl radical, an unstable free radical, not water.
• (D) H₂O₃: This is trioxidane or hydrogen trioxide, an unstable molecule, not water.

Final Answer: (A) H₂O