sentences: helium / neon / argon belong to noble gases family , group 18 on the periodic table & the chemical symbol for argon is ar & the chemical symbol for helium is he & the chemical symbol for neon is ne ->  he, ne, ar belong to noble gases family, group 18 on the periodic table  he, ne, ar belong to noble gases family, group 18 on the periodic table & elements in the same group on the periodic table of elements have similar properties -> he, ne, ar have similar properties