Chapter 2, Problem 2.11QP

Interpretation Introduction

Interpretation:

The mass number of iron that has $28$ neutrons should be determined.

Concept Introduction:

Mass number(A): Mass number of an element is sum of protons and neutrons of the atom.

$\text{A= Number of protons}\left(\text{P}\right)\text{ + Number of neutrons}\left(\text{n}\right)$

Consider an element X with atomic number and mass number,

${}_Z^A\text{X}$

Where,

A is mass number and Z is atomic number (number of proton or electron)