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10 questions from this quiz
1/121/121/12th the mass of a carbon-12 atom
The abundance of each isotope
A weighted average
ArArAr is weighted; mass number is one isotope
∑(isotope mass×abundance)total abundance\frac{\sum(\text{isotope mass} \times \text{abundance})}{\text{total abundance}}total abundance∑(isotope mass×abundance)
35.535.535.5
75%75\%75%
Different isotopes contribute to it
On the periodic table
Moles=MassAr or Mr\text{Moles} = \frac{\text{Mass}}{Ar \text{ or } Mr}Moles=Ar or MrMass
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