Question

1. State modern periodic law. List any two merits of long form of periodic

table over Mendeleev’s periodic table.


2. Find the oxidation number of Manganese in KMnO4.


3. Arrange the following elements in the increasing order of their atomic

size and increasing order of ionization energy

a) Li, K, Rb, Cs

b) Li, Ne, B, C​

Answer 1

Explanation:

1. the modern periodic law states that physical and chemical properties of an element is the periodic function of their atomic number.

1. it provides an easier way to remember all the elements and their properties by just knowing their atomic numbers and electronic configuration
2. in this table same position is alloted to each isotope of an element as all the isotopes of an element have same atomic number.

2. +7

3. I don't know

Answer 2

$\huge\bigstar\underbrace{\mathtt\red{Ã} \mathtt\red{Ñ} \mathtt\purple{S} \mathtt\blue{W} \mathtt\green{Ê} \mathtt\pink{R}}\bigstar$

1. the modern periodic law states that physical and chemical properties of an element is the periodic function of their atomic number.

it provides an easier way to remember all the elements and their properties by just knowing their atomic numbers and electronic configuration

in this table same position is alloted to each isotope of an element as all the isotopes of an element have same atomic number.

2. +7