Relative Atomic Mass (OCR GCSE Chemistry A, Combined (Gateway Science Suite)): Quizzes

$\frac{1}{12}$ the mass of a carbon-12 atom

The abundance of each isotope

A weighted average of all isotopes

$Ar$ is a weighted average; mass number is for one isotope

75%

35.5

Different isotopes contribute to it

On the periodic table

$\frac{(mass \times abundance) + ...}{total abundance}$

$\text{Moles} = \frac{\text{Mass}}{Ar \text{ or } Mr}$

10.2

Moles, empirical formulas, and $Mr$