Question

Explain the periodic trends in modern periodic table

Answer 1

Answer:

Major periodic trends include: electronegativity, ionization energy, electron affinity, atomic radius, melting point, and metallic character. Periodic trends, arising from the arrangement of the periodic table, provide chemists with an invaluable tool to quickly predict an element's properties.

Answer 2

$\huge\star{\blue{\underline{\mathfrak{Answer :-}}}}$

The following other periodic trends in Modern Periodic Table :-

1) Valency :-

Valency is the combining capacity of an element.

a) Variation of valency in a period :- First increases and decreases as the number of the valence electrons increases from 1 to 8.

b) Variation of valency in a group :- It remains the same because the valence electrons remains same in a group there for the valency also remains same.

2) Atomic Size :-

a) Variation of atomic size in a period :- It decreases because as we move from left to right in a period, the atomic number increases by 1 for each succeeding element. Addition of new electron takes place in same shell due to which it comes closer to the nucleus and hence the atomic size decreases.

b) Variation of atomic size in a group :- It increases because as we move down in a group, a new shell of electron is added at each succeeding element . As a result the distance between the nucleus and the last shell increases and the atomic size increases from top to bottom.

3) Metallic and Non-metallic character :-

a) Variation in a period (for metals) :- It decreases because the tendency to lose electrons decreases due to increase in nuclear charge.

Variation in a period (for non-metals) :- It increases because non metallic character increases due to increase in nuclear charge for gaining of electrons becomes easy.

b) Variation in a group (for metals) :- It increases because tendency to lose electrons increases due to increase in size and due to less attraction between nucleus and Valence Electrons.

Variation in a group (for non-metals) :- It decreases because tendency to gain electrons decreases due to less force of attraction because size increases down the group.

4) Chemical reactivity :-

For metals :-

In a period :- decreases

In a group :- increases

Reason for both :- Same as metallic behaviour

For non-metals :-

In a period :- increases

In a group :- decreases

Reason for both :- Same as non-metallic behaviour

____________________