Chapter 4, Problem 50A

Interpretation Introduction

Interpretation : The difference between the mass number and the atomic number of an atom is to be determined.

Concept Introduction : The smallest component of an element that maintains its identity during a chemical reaction is called an atom.

Answer to Problem 50A

The mass number gives the sum of protons and neutrons count of an atom while the atomic number gives only the protons count.

Explanation of Solution

The atomic number of an element is the total number of protons in its atom's nucleus.An element is identified by its atomic number.

The mass number is the sum of the protons and neutrons in an atom.

The mass number gives the protons and neutrons count of an atom while the atomic number gives only the protons count.

  $\text{Mass}\text{number}\text{=}\text{Atomic}\text{number}\text{+}\text{Number}\text{of}\text{neutrons}$

So, the difference between the mass number and an atomic number of an atom is that the number of neutrons present in the particular atom.