(a) Neon has two shells, both of which are completely filled with electrons (2 electrons in
K shell and 8 electrons in L shell).
(b) Magnesium has the electronic configuration 2, 8, 2.
(c) Silicon has a total of three shells, with four electrons in its valence shell (2 electrons
in K shell, 8 electrons in L shell and 4 electrons in M shell).
(d) Boron has a total of two shells, with three electrons in its valence shell (2 electrons in
K shell and 3 electrons in L shell).
(e) Carbon has twice as many electrons in its second shell as in its first shell (2 electrons
in K shell and 4 electrons in L shell).

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