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

. neon
.magnesium
. silicon
. boron
.beryllium
please mark it as brainly

Answer 2

magnesium has electronic configuration of 2,8,2 and same as the silicon has total of the 3 shell with the 4 number of the electrons in its valence shell and 2 electrons in K shel and 8 electron in the L shell and 4 electron in the part of the M shell . hope this answer give hand for the student to get an ideas of it.