Chapter 2.4, Problem 2.9Q

(a)

Interpretation Introduction

Interpretation:

The element $\text{He}$ name, its atomic number, and its atomic mass have to be given.

Concept Introduction:

Atomic number:  It is defined as number of protons present in an atom.  The symbol of atomic number is Z.

Atomic mass:  It is the weighted average of the masses of each isotope that makes up the element. Atomic mass is measured in atomic mass units (amu).

(b)

Interpretation Introduction

Interpretation:

The element $\text{F}$ name, its atomic number, and its atomic mass have to be given.

Concept Introduction:

Refer to part a.

(c)

Interpretation Introduction

Interpretation:

The element $\text{Mn}$ name, its atomic number, and its atomic mass have to be given.

Concept Introduction:

Refer to part a.