Chapter 6.2, Problem 8PP

Interpretation Introduction

(a)

Interpretation:

The group, period and the block of an atom with the configuration $[\text{Ne}]3s^2$ without using the periodic table needs to be determined.

Concept introduction:

The horizontal rows of periodic table are termed as periods and the vertical columns are termed as groups. There are 7 periods and 18 groups present in the periodic table. The periodic table has four blocks, s-block, p-block, d-block and f-block.

Answer to Problem 8PP

The element with configuration $[\text{Ne}]3s^2$ belongs to 3^rd period, 2^nd group and s-block of the periodic table.

Explanation of Solution

The electronic configuration of the element is $[\text{Ne}]3s^2$. In the electronic configuration, the number of highest energy level indicates the period number. So, in the element $[\text{Ne}]3s^2$, 3 indicates the period number. So, the element belongs to 3^rd period. For representative element, valence electrons indicate the group number. The number of valence electrons is 2 for the element. So, the group number is 2. As the element is present in group 2, it belongs to s-block of the periodic table.

(b)

Interpretation Introduction

Interpretation:

The group, period and the block of an atom with the configuration $[\text{He}]2s^2$ without using the periodic table needs to be determined.

Concept introduction:

The horizontal rows of periodic table are termed as periods and the vertical columns are termed as groups. There are 7 periods and 18 groups present in the periodic table. The periodic table has four blocks, s-block, p-block, d-block and f-block.

Answer to Problem 8PP

The element with configuration $[\text{He}]2s^2$ belongs to 2^nd period, 2^nd group and s-block of the periodic table.

Explanation of Solution

The electronic configuration of the element is $[\text{He}]2s^2$. In the electronic configuration, the number of highest energy level indicates the period number. So, in the element $[\text{He}]2s^2$, 2 indicate the period number. So, the element belongs to 2^nd period. For representative element, valence electrons indicate the group number. The number of valence electrons is 2 for the element. So, the group number for the element is 2. As the element is present in group 2, it belongs to s-block of the periodic table.

(c)

Interpretation Introduction

Interpretation:

The group, period and the block of an atom with the configuration $[\text{Kr}]5s^{2}4d^{10}5p^5$ without using the periodic table needs to be determined.

Concept introduction:

The horizontal rows of periodic table are termed as periods and the vertical columns are termed as groups. There are 7 periods and 18 groups present in the periodic table. The periodic table has four blocks, s-block, p-block, d-block and f-block.

Answer to Problem 8PP

The element with configuration $[\text{Kr}]5s^{2}4d^{10}5p^5$ belongs to 5^th period, 17^th group and p-block of the periodic table.

Explanation of Solution

The electronic configuration of the element is $[\text{Kr}]5s^{2}4d^{10}5p^5$. In the electronic configuration, the number of highest energy level indicates the period number. So, in the element $[\text{Kr}]5s^{2}4d^{10}5p^5$, the number of highest energy level is 5 which indicate the period number. So, the element belongs to 5^th period. For representative element, valence electrons indicate the group number. The number of valence electrons is 7 for the element. So, the group number for the element is 17. As the element is present in group 7, it belongs to p-block of the periodic table.