Chapter 11, Problem 54A

Interpretation Introduction

Interpretation: Reason for the atoms of the elements at the bottom of a given group of the periodic table to be larger than the atoms of the elements at the top of the same group needs to be explained.

Concept introduction:

A group in a periodic table is a vertical row that consists of elements with similar chemical properties and a shell is a region around the nucleus of an atom that consists of electrons.

Answer to Problem 54A

This is because as we move down the group a new shell gets added up at every step.

Explanation of Solution

The size of the atom of an element depends on the number of shells it contains. As we move down the group a new shell gets added up at each step due to which the size of the atom of an element increases.

Conclusion

It is because of the addition of a shell at every step that the size of the atom of the bottom elements is larger than the size of the atoms at the top.