Question

Which element has
(a) two shells, both of which are completely filled with electrons?
(b) the electronic configuration 2.8. 2?
(c) a total of three shells, with four electrons in its valence shell?
(d) a total of two shells, with three electrons in its valence shell?
(e) twice as many electrons in its second shell as in its first shell?​

Answer 1

(a) Neon (electronic configuration = 2,8)

(b) Magnesium

(c) Silicon ( electronic configuration is 2,8,4)

(d) Boron ( electronic configuration is 2,3)

(e) Carbon ( electronic configuration is 2,4)

I hope it is helpful!