Question

The molecular mass of carbon dioxide $\left(C{O}_2\right)$ is u.

• A. 28
• B. 32
• C. 44
• D. 56

Answer 1

The correct option is C 44

• Molecular mass is the sum of atomic masses of all the atoms present in the molecule.
• We know that atomic mass of carbon is 12 u and that of oxygen is 16 u.
• Thus, molecular mass of carbon dioxide ($C{O}_2$) = (atomic mass of C) + $2\times$ (atomic mass of O) = (12 + 32) = 44 u.