Question

how many electrons are in it's outermost shell. Also, what is meant the term "smaller moiety" in reference to the comparison of the Na+ to standard Na metal.@

Answer 1

smaller moiety means smaller "thing". Na+ is smaller than Na atom. There are 10 electrons in the outermost shell.

Answer 2

i dont think Na+ ion has 10 electron in the outermost shell, remember that an Na+ ion has the 1s orbital (which holds 2 electrons) and the 2s orbital (which holds 8), since the highest level is 2 in this case (2 from the '2's) we only count the electron in this level, thus 2s^8 implies that there are 8 electrons on the outermost shell...