Question

Carbon with mass numbere 12 and 14 are present
in the ratio of 3:1. Find the average mass
number of carbon.​

Answer 1

The ratio of the occurrence of the two isotopes of Carbon C-12 and C-14 is 3:1.

So, the average atomic mass number will be:  (12*3 + 14*1)/(3+1)

=>(36+14)/4 =>50/4

=>25/2 =>12.5 units

So, the average atomic mass number is 12.5