Answer:
The average atomic mass of given element is 20.18 amu.
Explanation:
Given data:
Abundance of 1st isotope mass 20 amu = 90.92%
Abundance of 2nd isotope mass 21 amu = 0.257%
Abundance of 3rd isotope mass 22 amu = 8.82%
Average atomic mass = ?
Solution:
Average atomic mass = (abundance of 1st isotope × its atomic mass) +(abundance of 2nd isotope × its atomic mass) + (abundance of 3rd isotope × its atomic mass) / 100
Average atomic mass = (90.92×20)+(0.257×21)+(8.82×22) /100
Average atomic mass = 1818.4 + 5.397 +194.04 / 100
Average atomic mass = 2017.819 / 100
Average atomic mass = 20.18 amu.
The average atomic mass of given element is 20.18 amu.
