Chapter 11, Problem 69A

(a)

Interpretation Introduction

Interpretation:

From the atomic number, electronic configuration is to be determined.

Concept Introduction:

The number of electrons in the atom is equal to the atomic number of the element. So, we can easily determine the electronic configuration by the atomic number.

The electrons are filled from lower to higher energy levels following the Aufbau principle.

Lower $(n+l)$ values correspond to lower orbital energies. If $(n+l)$ value for two orbitals is equal, the orbital with the lower n value has lower energy.

Where,

• $n=\text{ principle quantum number}$
• $l=\text{ azimuthal quantum number}$

Answer to Problem 69A

Electronic configuration of sodium $\left(Z=11\right)$ is $1s^{2}2s^{2}2p^{6}3s^1$ or $[Ne]3s^1$ .

Explanation of Solution

The order in which the orbitals are filled with electrons is: 1s< 2s< 2p<3s< 3p<4s< 3d<4p<5s< 4d< 5p< 6s< 4f<5d< 6p< 7s<5f<6d<7p and so on.

So, the electronic configuration of sodium $\left(Z=11\right)$ is $1s^{2}2s^{2}2p^{6}3s^1$ or $[Ne]3s^1$ .

(b)

Interpretation Introduction

Interpretation:

From the atomic number, electronic configuration is to be determined.

Concept Introduction:

The number of electrons in the atom is equal to the atomic number of the element. So, we can easily determine the electronic configuration by the atomic number.

The electrons are filled from lower to higher energy levels following the Aufbau principle.

Lower $(n+l)$ values correspond to lower orbital energies. If $(n+l)$ value for two orbitals is equal, the orbital with the lower n value has lower energy.

Where,

• $n=\text{ principle quantum number}$
• $l=\text{ azimuthal quantum number}$

Answer to Problem 69A

Electronic configuration of gallium $\left(Z=31\right)$

  $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{10}4s^{2}4p^1$ or $[Ar]3d^{10}4s^{2}4p^1$ .

Explanation of Solution

The order in which the orbitals are filled with electrons is: 1s< 2s< 2p<3s< 3p<4s< 3d<4p<5s< 4d< 5p< 6s< 4f<5d< 6p< 7s<5f<6d<7p and so on.

Electronic configuration of gallium $\left(Z=31\right)$

  $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{10}4s^{2}4p^1$ or $[Ar]3d^{10}4s^{2}4p^1$ .

(c)

Interpretation Introduction

Interpretation:

From the atomic number, the electronic configuration is to be determined.

Concept Introduction:

The number of electrons in the atom is equal to the atomic number of the element. So, we can easily determine the electronic configuration by the atomic number.

The electrons are filled from lower to higher energy levels following the Aufbau principle.

Lower $(n+l)$ values correspond to lower orbital energies. If $(n+l)$ value for two orbitals is equal, the orbital with the lower n value has lower energy.

Where,

• $n=\text{ principle quantum number}$
• $l=\text{ azimuthal quantum number}$

Answer to Problem 69A

The electronic configuration of phosphorous is $\left(Z=15\right)$

  $1s^{2}2s^{2}2p^{6}3s^{2}3p^3$ or $[Ne]3s^{2}3p^3$ .

Explanation of Solution

The order in which the orbitals are filled with electrons is: 1s< 2s< 2p<3s< 3p<4s< 3d<4p<5s< 4d< 5p< 6s< 4f<5d< 6p< 7s<5f<6d<7p and so on.

The electronic configuration of phosphorous is $\left(Z=15\right)$

  $1s^{2}2s^{2}2p^{6}3s^{2}3p^3$ or $[Ne]3s^{2}3p^3$ .

(d)

Interpretation Introduction

Interpretation:

From the atomic number, the electronic configuration is to be determined.

Concept Introduction:

The number of electrons in the atom is equal to the atomic number of the element. So, we can easily determine the electronic configuration by the atomic number.

The electrons are filled from lower to higher energy levels following the Aufbau principle.

Lower $(n+l)$ values correspond to lower orbital energies. . If $(n+l)$ value for two orbitals is equal, the orbital with the lower n value is said to have lower energy associated with it.

Where,

• $n=\text{ principle quantum number}$
• $l=\text{ azimuthal quantum number}$

Answer to Problem 69A

Electronic configuration of tin $\left(Z=50\right)$

  $1s^{2}2s^{2}2p^{6}3s^{2}3p^{3}3d^{10}4s^{2}4p^{6}5s^{2}4d^{10}5p^2$ or $[Kr]5s^{2}4d^{10}5p^2$ .

Explanation of Solution

The order in which the orbitals are filled with electrons is: 1s< 2s< 2p<3s< 3p<4s< 3d<4p<5s< 4d< 5p< 6s< 4f<5d< 6p< 7s<5f<6d<7p and so on.

Electronic configuration of tin $\left(Z=50\right)$

  $1s^{2}2s^{2}2p^{6}3s^{2}3p^{3}3d^{10}4s^{2}4p^{6}5s^{2}4d^{10}5p^2$ or $[Kr]5s^{2}4d^{10}5p^2$ .