Question

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 1

Answer:

there are 18 groups and 7 period in modern periodic table. as we move down a group the atomic size increases and metallic character also increases.

but as we from left to right it decreases and so does the metallic character