Chapter U1.24, Problem 13E

Interpretation Introduction

(a)

Interpretation:

The element whose electronic configuration is given has to be identified.

1s² 2s² 2p⁶3s²3p⁶4s²3d⁴

Concept introduction:

The electrons in an atom can be arranged in a shorthand notation form called electron configuration. Counting the number of electrons in the electron configuration will help us to know the atomic number of the atom. Each element has a unique atomic number.

The ending gives the exact location of the atom on the periodic table. The subscript tells the period number, the subshell letter tells the block and the superscript number tells the row number of that block.

Answer to Problem 13E

Chromium, Cr

Explanation of Solution

1s² 2s² 2p⁶3s²3p⁶4s²3d⁴ - To identify the element one has to simply look at the last subshell; 3d⁴. This element has valence electrons in subshell 3d. So it belongs to 4^th period, d block. Total number of electrons = 24. The superscript number tells the row number of that block; here it is 4 so group is 6(2s + 4d) on the periodic table. The element is hence chromium.

Interpretation Introduction

(b)

Interpretation:

The element whose electronic configuration is given has to be identified.

1s² 2s² 2p⁶3s²3p²

Concept introduction:

The electrons in an atom can be arranged in a shorthand notation form called electron configuration. Counting the number of electrons in the electron configuration will help us to know the atomic number of the atom. Each element has a unique atomic number.

The ending gives the exact location of the atom on the periodic table. The subscript tells the period number, the subshell letter tells the block and the superscript number tells the row number of that block.

Answer to Problem 13E

Silicon

Explanation of Solution

1s² 2s² 2p⁶3s²3p² - To identify the element one has to simply look at the last subshell; 3p². This element has valence electrons in subshell 3p. So it belongs to 3^rdperiod, in p block. Total number of electrons = 14. The superscript number tells the row number of that block; here it is 2 so group is 14 (2s + 10d + 2p) on the periodic table. The element is hence silicon.

Interpretation Introduction

(c)

Interpretation:

The element whose electronic configuration is given has to be identified.

1s² 2s² 2p³

Concept introduction:

The electrons in an atom can be arranged in a shorthand notation form called electron configuration. Counting the number of electrons in the electron configuration will help us to know the atomic number of the atom. Each element has a unique atomic number.

The ending gives the exact location of the atom on the periodic table. The subscript tells the period number, the subshell letter tells the block and the superscript number tells the row number of that block.

Answer to Problem 13E

Nitrogen

Explanation of Solution

1s² 2s² 2p³ - To identify the element one has to simply look at the last subshell; 2p³. This element has valence electrons in subshell 2p. So it belongs to 2ndperiod, in p block. Total number of electrons = 7. The superscript number tells the row number of that block; here it is 3 so group is 15 (2s + 10d + 3p) on the periodic table. The element is hence nitrogen.

Interpretation Introduction

(d)

Interpretation:

The element whose electronic configuration is given has to be identified.

1s² 2s² 2p⁶3s²3p⁶ 4s²3d¹⁰4p⁶5s²4d¹⁰ 5p⁶6s¹

Concept introduction:

The electrons in an atom can be arranged in a shorthand notation form called electron configuration. Counting the number of electrons in the electron configuration will help us to know the atomic number of the atom. Each element has a unique atomic number.

The ending gives the exact location of the atom on the periodic table. The subscript tells the period number, the subshell letter tells the block and the superscript number tells the row number of that block.

Answer to Problem 13E

Caesium

Explanation of Solution

1s² 2s² 2p⁶3s²3p⁶ 4s²3d¹⁰4p⁶5s²4d¹⁰ 5p⁶6s¹-To identify the element one has to simply look at the last subshell; 6s¹. This element has valence electrons in subshell 6s. So it belongs to 6thperiod, in s block. The superscript number tells the row number of that block; here it is 1 so group is 1 on the periodic table. The element is hence caesium.

Interpretation Introduction

(e)

Interpretation:

The element whose electronic configuration is given has to be identified.

1s² 2s² 2p⁶3s²3p⁶ 4s²3d¹⁰4p⁶5s²4d¹⁰ 5p⁶6s²4f¹⁴5d¹⁰6p²-

Concept introduction:

The electrons in an atom can be arranged in a shorthand notation form called electron configuration. Counting the number of electrons in the electron configuration will help us to know the atomic number of the atom. Each element has a unique atomic number.

The ending gives the exact location of the atom on the periodic table. The subscript tells the period number, the subshell letter tells the block and the superscript number tells the row number of that block.

Answer to Problem 13E

Lead

Explanation of Solution

1s² 2s² 2p⁶3s²3p⁶ 4s²3d¹⁰4p⁶5s²4d¹⁰ 5p⁶6s²4f¹⁴5d¹⁰6p²-To identify the element one has to simply look at the last subshell; 3p². This element has valence electrons in subshell 6p. So it belongs to 6^thperiod, in p block. The superscript number tells the row number of that block; here it is 2 so group is 14 (2s + 10d + 2p) on the periodic table. The element is hence lead.

Interpretation Introduction

(f)

Interpretation:

The element whose electronic configuration is given has to be identified.

[Kr] 5s²4d⁹

Concept introduction:

The electrons in an atom can be arranged in a shorthand notation form called electron configuration. Counting the number of electrons in the electron configuration will help us to know the atomic number of the atom. Each element has a unique atomic number.

The ending gives the exact location of the atom on the periodic table. The subscript tells the period number, the subshell letter tells the block and the superscript number tells the row number of that block.

Answer to Problem 13E

Silver

Explanation of Solution

[Kr] 5s²4d⁹ - The noble gas that comes before the element is krypton. The last subshell filled is5s² and 4d⁹. This element has valence electrons in subshell 5. So it belongs to 5^thperiod, in d block. The superscript number tells the row number of that block; here it is 9 so group is 11 (2s + 9d) on the periodic table. The element is hence silver.