Question

Which atom is most likely to form a 2+ ion? Zn, Al, S, Na, N, cannot be determined

Answer 1

Look at the periodic table. Zn is in group 12 (or II), Al in 13 (or III), S in 16 (or VI), Na in 1(or I), N in at(or V). For numbers <10, I, II, III, etc. that's the possible valence. For numbers >10, it's the second number (12, 13, etc). So your answer is >>>>>>.