Question

1 amu or 1 u is defined as:

• A. $\frac{1}{16}$ the mass of oxygen-16 atom
• B. $\frac{1}{14}$ the mass of nitrogen-7 atom
• C. $\frac{1}{12}$ the mass of one carbon12 atom
• D. $\frac{1}{12}$ the mass of one carbon14 atom

Answer 1

The correct option is C $\frac{1}{12}$ the mass of one carbon12 atom

1 u is defined with respect to carbon atom. It is useful for reporting of mass of subatomic particles like proton and neutron.
$1u=\frac{\text{Mass of C-12 atom}}{12}$