Selina Concise Chemistry Class 10 ICSE Solutions Chapter 1 - Periodic Table, Periodic Properties and Variations of Properties
Selina Concise Chemistry Class 10 ICSE Solutions Periodic Table, Periodic Properties and Variations of Properties Selina Concise Chemistry Class 10 ICSE Solutions Periodic Table, Periodic Properties and Variations of Properties Exercise Intext 1 1. Solution 1. (a) The modern periodic law states that “The properties of elements are the periodic functions of their atomic number.” Henry Moseley put forward the modern periodic law. (b) A tabular arrangement of the elements in groups (vertical columns) and periods (horizontal rows) highlighting the regular trends in properties of elements is called a Periodic Table. Modern Periodic table has 7 periods and 18 groups. 2. Elements of group 1 and elements of group 17 both have valency1. Explain. Solution 2. Valency is the combining capacity of the atom of an element. It is equal to the number of electrons an atom can donate or accept or share. It is just a number and does not have a positive or negative sign. Group 1...