The relative mass of Al2O3=2*27+16*3=102
n=mass/relative mass=141.98/102=1.39 mol
Answer:The average atomic mass of an element is the sum of the masses of its isotopes, each multiplied by its natural abundance (the decimal associated with percent of atoms of that element that are of a given isotope).
Explanation:try to find what i ment and think you will get the answer
Answer:
Hope the above picture might help you :)
