Name the first and last element in period 2

Which of the following are the first and last elements in a spinal reflex?

The following questions refer to the periodic table : Name the second last element of the period 3.

Name the first and last alkali metals

Name the first and second elements of groups 14.

Name first element of period 7

Name the first two elements of group 17.

a. Name the most metallic element in second period and most non-metallic element. b. The element with (i) largest atomic radius and (ii) smallest atomic radius in third period. c. The element having general electronic configuration ns^(2)np^(4) in fourth period.

Name the first element of group 13.

Name or state with reference to the elements of the modern periodic table. The formula of the sulphite of the element in period-3, group 1 [IA].

What is the main characteristic of the last elements in the periods of a periodic table? What is the general name of such elements ?