Chapter 7, Problem 65A

(a)

Interpretation Introduction

Interpretation: To determine the electronic configuration of given atoms and ions.

Concept Introduction: The placement of electrons inside orbitals around a nuclear nucleus is known as electronic configuration, also known as electronic structure as well as electron configuration.

Answer to Problem 65A

The electronic configuration of the Ar atom is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^6$

The electronic configuration of the potassium ion ( ${\text{K}}^{\text{+}}$ ) will be ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}$ .

The electronic configuration of calcium ion ${\text{Ca}}^{\text{2+}}$ is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}$

Explanation of Solution

• The atomic number of Ar atom =18. The electronic configuration of the chromium Ar atom is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^6$ .
• The atomic number of potassium is 19. After losing one electron, the new atomic number of potassium will be 18. The electronic configuration of ( ${\text{K}}^{\text{+}}$ ) will be ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}$
• The atomic number of Ca of 20. After losing two electrons, the new atomic number of ${\text{Ca}}^{\text{2+}}$ will be ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}$ .

(b)

Interpretation Introduction

Interpretation: To determine the electronic configuration of given atoms and ions.

Concept Introduction: The placement of electrons inside orbitals around a nuclear nucleus is known as electronic configuration, also known as electronic structure as well as electron configuration.

Answer to Problem 65A

The electronic configuration of the Ne atom is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}$

The electronic configuration of the sodium ion ( ${\text{Na}}^{\text{+}}$ ) will be ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}$ .

The electronic configuration of magnesium ion ${\text{Mg}}^{\text{2+}}$ is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}$

The electronic configuration of aluminium ion ${\text{Al}}^{\text{3+}}$ is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}$

Explanation of Solution

• The atomic number of Neon (Ne) atom =10. The electronic configuration of the chromium Ne atom is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}$ .
• The atomic number of sodium is 11. After losing one electron, the new atomic number of potassium will be 10. The electronic configuration of ( ${\text{Na}}^{\text{+}}$ ) will be ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}$
• The atomic number of magnesium ( $\text{Mg}$ ) of 12. After losing two electrons, the new atomic number of ${\text{Mg}}^{\text{2+}}$ will be 10. The electronic configuration of ${\text{Mg}}^{\text{2+}}$ will be ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}$ .
• The atomic number of aluminum $\text{(Al)}$ is 13. After losing three electrons, the new atomic number of aluminum will be 10. The electronic configuration of ${\text{Al}}^{\text{3+}}$ will be ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}$ .