Question

A sample of Element X is found to contain 67.25% of isotope type 1 (85.91) and 32.75% of isotope type 2 (87.91). Calculate the average atomic mass.

Answer 1

The average atomic mass is 86.565

Step-by-step explanation:

An element's average atomic mass is the sum of the products of the masses of the isotopes of the element and their percentage abundance divided by 100

The average atomic mass of the Element X is given as follows;

Isotope type 1 (85.91) ×

Isotope
`{}` Abundance (%) Mass /100 Portion of average mass

Type 1
`{}` 67.25 × 85.91 ÷ 100 57.774475

Type 2
`{}` 32.75 × 87.91 ÷ 100 28.790525

`{}` Average atomic mass = 86.565

The average atomic mass = 86.565.