Question

An element X belongs to the 3rd period and 1st group of the periodic table. The atomic number
of the element will possibly be:

0 1
O 3
O 11
O 10​

Answer 1

Answer:

11

Explanation:

atomic no is of Na i.e 11

1 st group is of alkali metals

so 2 nd period element is Li having atomic no 3

so 3 rd period element atomic no is = 3 + 8 = 11