Ans.
1. The modern periodic table has seven horizontal rows called the periods and eighteen vertical columns called the groups. This arrangement results in the formation of boxes in which each boy corresponds to the position of an element.
2. In addition to these seven rows, two series are shown separately at the bottom of the periodic table. The first row is lanthanide series and the second row is actinide series.
3. The entire periodic table is divided into four blocks as follows:
s-block: contains group 1 and 2 elements.
p-block: contains group 13 to 18 elements.
d-block: contains group 3 to 12 elements. (transition elements)
f-block: contains lanthanide and actinide series.
4. A zig - zag line is drawn in the p-block of the periodic table. Metals lie on the left side while nonmetals lie on the right side of this line. Metalloids lie along the border of this line.