Chapter 4, Problem 57A

Interpretation Introduction

Interpretation : The atomic mass of an element is to be explained.

Concept Introduction : The atomic mass is the weighted average mass of the atoms in a naturally occurring sample of an element.

Answer to Problem 57A

The weighted average mass of the atoms in a naturally occurring sample of an element is the atomic mass.

The formula to calculate atomic mass is given as:

  $\text{Atomic mass}\text{=}\text{Isotope}\text{mass number}\times \text{Natural percent abundance}$

Explanation of Solution

The weighted average mass of the atoms in a naturally occurring sample of an element is the atomic mass.

The mass and relative abundance of isotopes as they appear in nature are both reflected in the weighted average mass.

For the calculation of atomic mass, multiply each isotope's mass by its natural abundance, represented as a decimal, and add on the products.

The formula to calculate atomic mass is given as:

  $\text{Atomic mass}\text{=}\text{Isotope}\text{mass number}\times \text{Natural percent abundance}$