19.9% of all Boron atoms are Boron-10. 80.1% are Boron-11.
Calculate the approximated relative atomic mass of Boron, to one decimal place.
Magnesium has three of it's own isotopes.
78.7% is Magnesium-24.
10.13% is Magnesium-25.
11.17% is Magnesium-26.
Calculate the relative atomic mass of Magnesium, to two decimal places.
Element A occurs naturally in the environment.
Scientists have found 612 atoms of A-15, 829 atoms of A-16, and 244 atoms of A-17.
Calculate the relative atomic mass of the element A to two decimal places.