1.수소/2.He헬륨/3.Li리튬/5.B붕소/6.C탄소/7.N질소/8.O.산소/9.F플루오르/10.Ne네온/11.Na나트륨/12.Mg마그네슘/13.AI알루미늄/14.Si규소/15.P인/공간이부족..
당신은 어느 그룹입니까?