Chapter 5, Problem 21PE

(a)

Interpretation Introduction

Interpretation:

The number of protons, neutrons and electrons in ${}^{\text{63}}\text{Cu}$ has to be given.

Concept Introduction:

Mass number is the sum of the protons and neutrons in the nucleus.

Atomic number is the number of protons present in the nucleus.

For an element $\text{E,}$ the top left number represents the mass number and the bottom left number represents the atomic number.

The letter A represents mass number.

The letter Z represents atomic number.

Answer to Problem 21PE

The number of protons in ${}^{\text{63}}\text{Cu}$ is $\text{29}\text{.}$

The number of electrons in ${}^{\text{63}}\text{Cu}$ is $\text{29}\text{.}$

The number of neutrons in ${}^{\text{63}}\text{Cu}$ is $\text{34}\text{.}$

Explanation of Solution

The atomic number of ${}^{\text{63}}\text{Cu}$ is $\text{29}\text{.}$

The mass number of ${}^{\text{63}}\text{Cu}$ is $\text{63}\text{.}$

Atomic number of an element tells about the number of protons present.

  $\text{Atomic}\text{number=Number}\text{of}\text{protons}$

The number of protons present will be equal to the number of electrons.

  $\text{Number}\text{of}\text{protons=Number}\text{of}\text{electrons}$

Atomic number of ${}^{\text{63}}\text{Cu}$ is $\text{29}\text{.}$  Therefore, the number of protons is $\text{29}\text{.}$  The number of electrons is $\text{29}\text{.}$

The number of neutrons is the difference between the mass number and the atomic number.

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

The number of neutrons is calculated as,

  Number of neutrons=$\text{63-29}$

  Number of neutrons=$\text{34}$

The number of protons in ${}^{\text{63}}\text{Cu}$ is $\text{29}\text{.}$

The number of electrons in ${}^{\text{63}}\text{Cu}$ is $\text{29}\text{.}$

The number of neutrons in ${}^{\text{63}}\text{Cu}$ is $\text{34}\text{.}$

(b)

Interpretation Introduction

Interpretation:

The number of protons, neutrons and electrons in ${}^{\text{32}}\text{S}$ has to be given.

Concept Introduction:

Refer to part (a).

Answer to Problem 21PE

The number of protons in ${}^{\text{32}}\text{S}$ is $\text{16}\text{.}$

The number of electrons in ${}^{\text{32}}\text{S}$ is $\text{16}\text{.}$

The number of neutrons in ${}^{\text{32}}\text{S}$ is $\text{16}\text{.}$

Explanation of Solution

The atomic number of ${}^{\text{32}}\text{S}$ is $\text{16}\text{.}$

The mass number of ${}^{\text{32}}\text{S}$ is $\text{32}\text{.}$

Atomic number of an element tells about the number of protons present.

  $\text{Atomic}\text{number=Number}\text{of}\text{protons}$

The number of protons present will be equal to the number of electrons.

  $\text{Number}\text{of}\text{protons=Number}\text{of}\text{electrons}$

Atomic number of ${}^{\text{32}}\text{S}$ is $\text{16}\text{.}$  Therefore, the number of protons is $\text{16}\text{.}$  The number of electrons is $\text{16}\text{.}$

The number of neutrons is the difference between the mass number and the atomic number.

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

The number of neutrons is calculated as,

  Number of neutrons=$\text{32-16}$

  Number of neutrons=$\text{16}$

The number of protons in ${}^{\text{32}}\text{S}$ is $\text{16}\text{.}$

The number of electrons in ${}^{\text{32}}\text{S}$ is $\text{16}\text{.}$

The number of neutrons in ${}^{\text{32}}\text{S}$ is $\text{16}\text{.}$

(c)

Interpretation Introduction

Interpretation:

The number of protons, neutrons and electrons in ${}^{55}\text{Mn}$ has to be given.

Concept Introduction:

Refer to part (a).

Answer to Problem 21PE

The number of protons in ${}^{55}\text{Mn}$ is $\text{25}\text{.}$

The number of electrons in ${}^{55}\text{Mn}$ is $\text{25}\text{.}$

The number of neutrons in ${}^{55}\text{Mn}$ is $\text{30}\text{.}$

Explanation of Solution

The atomic number of ${}^{55}\text{Mn}$ is $\text{25}\text{.}$

The mass number of ${}^{55}\text{Mn}$ is $\text{55}\text{.}$

Atomic number of an element tells about the number of protons present.

  $\text{Atomic}\text{number=Number}\text{of}\text{protons}$

The number of protons present will be equal to the number of electrons.

  $\text{Number}\text{of}\text{protons=Number}\text{of}\text{electrons}$

Atomic number of ${}^{55}\text{Mn}$ is $\text{25}\text{.}$  Therefore, the number of protons is $\text{25}\text{.}$  The number of electrons is $\text{25}\text{.}$

The number of neutrons is the difference between the mass number and the atomic number.

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

The number of neutrons is calculated as,

  Number of neutrons=$\text{55-25}$

  Number of neutrons=$\text{30}$

The number of protons in ${}^{55}\text{Mn}$ is $\text{25}\text{.}$

The number of electrons in ${}^{55}\text{Mn}$ is $\text{25}\text{.}$

The number of neutrons in ${}^{55}\text{Mn}$ is $\text{30}\text{.}$

(d)

Interpretation Introduction

Interpretation:

The number of protons, neutrons and electrons in ${}^{\text{39}}\text{K}$ has to be given.

Concept Introduction:

Refer to part (a).

Answer to Problem 21PE

The number of protons in ${}^{\text{39}}\text{K}$ is $\text{19}\text{.}$

The number of electrons in ${}^{\text{39}}\text{K}$ is $\text{19}\text{.}$

The number of neutrons in ${}^{\text{39}}\text{K}$ is $\text{20}\text{.}$

Explanation of Solution

The atomic number of ${}^{\text{39}}\text{K}$ is $\text{19}\text{.}$

The mass number of ${}^{\text{39}}\text{K}$ is $\text{39}\text{.}$

Atomic number of an element tells about the number of protons present.

  $\text{Atomic}\text{number=Number}\text{of}\text{protons}$

The number of protons present will be equal to the number of electrons.

  $\text{Number}\text{of}\text{protons=Number}\text{of}\text{electrons}$

Atomic number of ${}^{\text{39}}\text{K}$ is $\text{19}\text{.}$  Therefore, the number of protons is $\text{19}\text{.}$  The number of electrons is $\text{19}\text{.}$

The number of neutrons is the difference between the mass number and the atomic number.

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

The number of neutrons is calculated as,

  Number of neutrons=$\text{39-19}$

  Number of neutrons=$\text{20}$

The number of protons in ${}^{\text{39}}\text{K}$ is $\text{19}\text{.}$

The number of electrons in ${}^{\text{39}}\text{K}$ is $\text{19}\text{.}$

The number of neutrons in ${}^{\text{39}}\text{K}$ is $\text{20}\text{.}$