The electronic configuration of the elements A, B, C, Dare given below.
A – 1s2 2s2 2p6 3s2 3p4
B – 1s2 2s2 2p6 3s2
C – 1s2 2s2 2p6 3s2 3p5
D – 1s2 2s2 2p6 3s1
a. Which of these elements show +2 oxidation state?
b. Which metal belongs to 17th group?
c. Which is the period number of the element A ? What is the basis of your findings?
d. Which of these elements can form basic Oxides?