Question

An unknown element X has two isotopes; 70% have a mass of 26 and 30% a mass of 30. What would be closest to the

average atomic mass for element X?

Answer 1

27.2 a.m.u

Step-by-step explanation:

Isotope of an element is its tendency to exist in two or more forms. Thus, the average atomic mass of the element is required. And this can be calculated by adding the individual product of the percentage isotope and its mass.

The average atomic mass of the element can be determined by:

= (70% x 26) + (30% x 30)

= (0.7 x 26) + (0.3 x 30)

= 18.2 + 9

= 27.2

Thus, the average atomic mass of element X is 27.2 a.m.u