elements are all from the first group of the periodic table
one_of_chemical_elements is hydrogen. list_of_elements is list. one_of_chemical_elements is mercury. periodic_table is table. one_of_chemical_elements is chromium. one_of_chemical_elements is nitrogen. one_of_chemical_elements is helium. group_11_elements is coinage_metals. group_1_elements is alkali_metals. each_element_in_periodic_table has number_associated_with