What is the significance of atomic number in modern classification of elements? Explain with the help of an example.
The modern periodic law states that “the physical and chemical properties of the elements are the periodic function of their atomic numbers”.
The atomic number helps in arranging the elements according to their electronic configuration. Since the number of valence electrons is the same, elements placed in the same group show similar chemical properties.
For example, if we take the element lithium (Li), its atomic number is 3. Its electronic configuration is (2,1). As it has one valence electron, it is placed in the first group of the periodic table. Similarly, all the elements having one valence electron will be placed in group 1, and they show similar chemical properties. In this manner, the classification of elements is made according to the electronic configuration of the elements.
The modern periodic law states that “the physical and chemical properties of the elements are the periodic function of their atomic numbers”.
The atomic number helps in arranging the elements according to their electronic configuration. Since the number of valence electrons is the same, elements placed in the same group show similar chemical properties.
For example, if we take the element lithium (Li), its atomic number is 3. Its electronic configuration is (2,1). As it has one valence electron, it is placed in the first group of the periodic table. Similarly, all the elements having one valence electron will be placed in group 1, and they show similar chemical properties. In this manner, the classification of elements is made according to the electronic configuration of the elements.
