The atomic mass of the element = 24.309547
Given
Isotopes of Mg
Required
The atomic mass
Solution
Atomic mass is the average atomic mass of all its isotopes
Mass atom X = mass isotope 1 . % + mass isotope 2.% ..
The atomic mass of the element(Mg) :
= 23.98504 . 0.7870 + 24.98584 . 0.1013 + 25.98259 . 0.1117
= 18.876226 + 2.531066 + 2.902255
= 24.309547