Question

The molecular mass of $C{H}_{3}C{H}_{2}OH$ is ______.

• A. 50 u
• B. 35 u
• C. 70 u
• D. 46 u

Answer 1

The correct option is D

46 u

Molecular mass of a substance is the sum of the atomic masses of all the constituent atoms.
The atomic mass of carbon (C) = 12 u
The atomic mass of hydrogen (H) = 1 u
The atomic mass of oxygen (O) = 16 u

$\therefore$ The molecular mass of $C{H}_{3}C{H}_{2}OH$ = 2 $\times$ atomic mass of carbon + 6 $\times$ atomic mass of hydrogen + 1 $\times$atomic mass of oxygen
= $(2\times 12)+(6\times 1)+(1\times 16)$
= 46 u.