Question

Sulfur has 4 isotopes: sulfur-32 is 95.0%, sulfur-33 is 0.76%, sulfur-34 is 3.22%, and sulfur-36 is 0.89% abundant. calculate its average atomic mass. express your answer with five sig figs.

Answer 1

Answer:- Average atomic mass is 32.066.

Solution:- To calculate the average atomic mass the percentages of the isotopes are converted to decimals and multiplied by their respective isotopic masses. We do this for all the isotopes and take the sum as:

average atomic mass = 32(0.95)+33(0.0076)+34(0.0322)+36(0.0089)

= 30.4+0.2508+1.0948+0.3204

= 32.066

So, the atomic mass of sulfur is 32.066.

Answer 2

Answer :The average atomic mass of Sulfur is 32.066 amu.

Explanation :

The average atomic mass of an element is the total of atomic mass of an isotope multiplied by its natural abundance.

The formula for average atomic mass of S can be written as follows.

Average Atomic Mass = (Atomic mass of S-32 * Abundance of S-32) + (Atomic mass of S-33 * Abundance of S-33) + (Atomic mass of S-34 * Abundance of S-34) + (Atomic mass of S-36 * Abundance of S-36)

For calculation purpose, we will use atomic masses same as mass numbers .

S-32 = 32 amu ; Abundance = 0.95

S-33 = 33 amu ; Abundance = 0.0076

S-34 = 34 amu ; Abundance = 0.0322

S-36 = 36 amu ; Abundance = 0.0089

Let us plug the above values in average atomic mass equation.

Average Atomic Mass = $(32amu \times 0.95) + (33amu \times 0.0076) + (34amu \times 0.0322) + (36amu \times 0.0089)$

Average Atomic Mass = $(30.4amu)+(0.2508amu)+(1.0948amu)+(0.3204amu)$

Average Atomic Mass = 32.066 amu

The average atomic mass of Sulfur is 32.066 amu