# Question #4c34a

Jun 4, 2017

Relative atomic mass (${A}_{\textrm{r}}$) is the ratio of the average mass of an atom of an element to 1 u.

#### Explanation:

Relative atomic mass has no units.

For example, the relative atomic mass of chlorine is

${A}_{\textrm{r}} = \left(35.45 \textcolor{red}{\cancel{\textcolor{b l a c k}{\text{u"))))/(1 color(red)(cancel(color(black)("u}}}}\right) = 35.45$

Thus, relative atomic mass has the same numerical value as the average atomic mass on the Periodic Table.