Multiple ChoiceWhich element on the periodic table has 4 energy levels and 8 valence electrons?66views
Multiple ChoiceWhich of the following lists contains the eight most abundant elements in Earth's crust?52views
Multiple ChoiceWhich properties of gallium was Mendeleev able to predict before its discovery?58views
Multiple ChoiceWhich group of elements on the periodic table exhibits both metallic and nonmetallic physical and chemical properties?45views