Question

The gram molecular mass of oxygen is

• A. 16g
• B. 32g
• C. 64g
• D. 48g

Answer 1

The correct option is B

32g

• Molecular mass of a substance is the total mass of all the atoms present in that substance .
• The unit of atomic mass and molecular mass is 'u'" (unified mass).
• The Mole is the same amount of substance that contains the same number of particles ( atoms, ions, molecules etc) as there are atoms in 12g 0f carbon atom
• The mass of one mole of a substance is equal to its relative atomic mass or molecular mass in grams..
• It is also called molar mass.

Explanation for correct answer

• Atomic mass of one atom oxygen is 16u.
• The molecular mass of oxygen molecule (O₂) is (16x2 ) = 32u.
• The gram molecular mass means the molecular mass expressed in gram.
• Therefore,the gram molecular mass of oxygen is 32g.