Answer
(a) $13.003~u$
(b) $2.16\times 10^{-26}~kg$
Work Step by Step
(a) We can find the mass of one $^{13}C$ atom:
$m = 13.003~g/mol\times \frac{1~u}{1~g/mol} = 13.003~u$
(b) We can find the mass of one $^{13}C$ atom:
$m = \frac{13.003\times 10^{-3}~kg/mol}{6.022\times 10^{23}~atoms/mol} = 2.16\times 10^{-26}~kg$
