If bromine atom is available in the form of, say, two isotopes35 Br79 (49.7persent) and 35Br 81 (50.3persent),

Question

If bromine atom is available in the form of, say, two isotopes  ₃₅Br⁷⁹ (49.7%) and ₃₅Br⁸¹ (50.3%), calculate the average atomic mass of bromine atom.

Answer 1

The average atomic mass of bromine 

= (79 x 49.7)+ (81 x 50.3)/100 

= (3926.3 + 4074.3)/100 

= 8000.6/100 

= 80 u