Chapter 4, Problem 74A

How many electrons, protons, and neutrons are contained in each atom?
a. gallium-69   c. titanium-48
b. fluorine-23   d. tantalum-181

Interpretation Introduction

(a)

Interpretation:

Electrons, protons and neutrons in an atom of gallium-69 is to be calculated.

Concept introduction:

Number of protons present in an atom is also referred as Atomic number of an atom. Total number of protons and neutrons present in the nucleus of an atom is known as mass number.

Answer to Problem 74A

Gallium-69

$\begin{array}{l}\text{Number of protons = 31}\hfill \\ \text{Number of electrons = 31}\hfill \\ \text{Number of neutrons = 38}\hfill \end{array}$

Explanation of Solution

Gallium- 69

Atomic number of Gallium is 31

$\begin{array}{l}\text{Atomic number = Number of protons}\hfill \\ \text{Number of protons = 31}\hfill \end{array}$

$\begin{array}{l}\text{Number of electrons = Number of protons}\hfill \\ \text{Number of electrons = 31}\hfill \end{array}$

Mass number of Gallium is 69

$\begin{array}{l}\text{Mass number = Number of protons + number of neutrons}\hfill \\ \text{Number of neutrons = Mass number – Number of protons}\hfill \\ \text{Number of neutrons = 69 – 31}\hfill \\ \text{Number of neutrons = 38}\hfill \end{array}$

Interpretation Introduction

(b)

Interpretation:

Electrons, protons and neutrons in an atom of titanium-48 is to be calculated.

Concept introduction:

Number of protons present in an atom is also referred as Atomic number of an atom. Total number of protons and neutrons present in the nucleus of an atom is known as mass number.

Answer to Problem 74A

Titanium-48

$\begin{array}{l}\text{Number of protons = 22}\hfill \\ \text{Number of electrons = 22}\hfill \\ \text{Number of neutrons = 26}\hfill \end{array}$

Explanation of Solution

Titanium-48

Atomic number of Titanium is 22

$\begin{array}{l}\text{Atomic number = Number of protons}\hfill \\ \text{Number of protons = 22}\hfill \end{array}$

$\begin{array}{l}\text{Number of electrons = Number of protons}\hfill \\ \text{Number of electrons = 22}\hfill \end{array}$

Mass number of Titanium is 48

$\begin{array}{l}\text{Mass number = Number of protons + number of neutrons}\hfill \\ \text{Number of neutrons = Mass number – Number of protons}\hfill \\ \text{Number of neutrons = 48 – 22}\hfill \\ \text{Number of neutrons = 26}\hfill \end{array}$

Interpretation Introduction

(c)

Interpretation:

Electrons, protons and neutrons in an atom of fluorine-23 is to be calculated.

Concept introduction:

Number of protons present in an atom is also referred as Atomic number of an atom. Total number of protons and neutrons present in the nucleus of an atom is known as mass number.

Answer to Problem 74A

Fluorine-23

$\begin{array}{l}\text{Number of protons = 9}\hfill \\ \text{Number of electrons = 9}\hfill \\ \text{Number of neutrons = 14}\hfill \end{array}$

Explanation of Solution

Fluorine-23

Atomic number of Fluorine is 9

$\begin{array}{l}\text{Atomic number = Number of protons}\hfill \\ \text{Number of protons = 9}\hfill \end{array}$

$\begin{array}{l}\text{Number of electrons = Number of protons}\hfill \\ \text{Number of electrons = 9}\hfill \end{array}$

Mass number of Fluorine is 23

$\begin{array}{l}\text{Mass number = Number of protons + number of neutrons}\hfill \\ \text{Number of neutrons = Mass number – Number of protons}\hfill \\ \text{Number of neutrons = 23 – 9}\hfill \\ \text{Number of neutrons = 14}\hfill \end{array}$

Interpretation Introduction

(d)

Interpretation:

Electrons, protons and neutrons in an atom of tantalum-181 is to be calculated.

Concept introduction:

Number of protons present in an atom is also referred as Atomic number of an atom. Total number of protons and neutrons present in the nucleus of an atom is known as mass number.

Answer to Problem 74A

Tantalum-181

$\begin{array}{l}\text{Number of protons = 73}\hfill \\ \text{Number of electrons = 73}\hfill \\ \text{Number of neutrons = 108}\hfill \end{array}$

Explanation of Solution

Tantalum-181

Atomic number of Tantalum is 73

$\begin{array}{l}\text{Atomic number = Number of protons}\hfill \\ \text{Number of protons = 73}\hfill \end{array}$

$\begin{array}{l}\text{Number of electrons = Number of protons}\hfill \\ \text{Number of electrons = 73}\hfill \end{array}$

Mass number of Tantalum is 181

$\begin{array}{l}\text{Mass number = Number of protons + number of neutrons}\hfill \\ \text{Number of neutrons = Mass number – Number of protons}\hfill \\ \text{Number of neutrons = 181 – 73}\hfill \\ \text{Number of neutrons = 108}\hfill \end{array}$