Example image of eyePlorer eyePlorer map for 'Period 8 element': Chemical element Extension of the periodic table beyond the seventh period Period (periodic table) International Union of Pure and Applied Chemistry Systematic element name Proton drip line Mendeleev's predicted elements 129 (number) Group 4 element 133 (number) 139 (number) 127 (number) Eka-actinium P8 Ute Uth Uto Electron shell