Question

The relative atomic mass of an element A is
16.2. There are two isotopes 16 A and 18A of the
element. Calculate the percentage of these two
isotopes present in the element.​

Answer 1

Answer:

Let the percentage of isotope X-16 = x

 The percentage of isotope X-18 = 100-x

Relative atomic mass = 16.2

Formula:  Relative atomic mass =  

Putting the value of parameter in above formula

 16.2 = [16x + 18(100-x)] /100

The value of x is 90

Therefore percentage of isotope of mass no. 16 is 90%, while for isotope-18 is 10%