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

There are 18 groups and 7 periods in the Modern Periodic Table.
(a) * Atomic size increase
     *  Metallic character increases
(b) * Atomic size decreases
      * Metallic character decreases