Chapter 3, Problem 3.21E

Interpretation Introduction

Interpretation:

An element of period $5$ that has similar chemical properties to sodium is to be predicted and number of valence electrons present in an element of period $6$ and in silicon is to be stated.

Concept introduction:

The elements in a modern periodic table are arranged in an increasing order of their atomic number. In the modern periodic table, the horizontal rows are known as periods, whereas vertical columns are known as groups. There are $7$ periods and $18$ groups in a modern periodic table.