How many groups and periods are there in the modern Periodic Table ? How do the atomic size and metallic character of elements vary as we move : (a) down a group and (b) from left to right in a period.

How many groups and periods are there in the modern Periodic Table ? H

1.	How many groups and periods are there in the modern Periodic Table ? How do the atomic size and metallic character of elements vary as we move : (a) down a group and (b) from left to right in a period.
Answer» Solution :There are 18 groups and 7 PERIODS in the modern Periodic Table. (a) On moving down a group, the atomic SIZE increases and metallic character also increases. (B) On moving from LEFT to right in a period, the atomic size decreases and the metallic character also decreases.