Ca belongs to group 2 in the periodic table.
the electronic configuration of Ca is - 1s² 2s² 2p⁶ 3s² 3p⁶ 4s²
Ca has 2 valence electrons in its outermost shell. Octet rule is when the outermost shell of the atom is complete with 8 electrons, that means both s and p subshells are complete.
for Ca to obey the octet rule its outermost shell should have 8 electrons.
therefore Ca should give up the 2 electrons in its outermost shell.
then the 3rd energy shell is the outermost shell with 8 electrons.
the correct answer is C. It gives up electrons.
