Assuming that elements are formed to complete the seventh period, what would be the atomic number of — Periodic Table and Periodicity Chemistry Question

💡 Solution & Explanation

Step 1: The seventh period concludes with the noble gas Oganesson, which has an atomic number of Z=118. Step 2: The eighth period starts with the alkali metal (Group 1) at Z=119. Step 3: Following the alkali metal, the alkaline earth metal (Group 2) in the eighth period will have an atomic number of Z = 119 + 1 = 120.