• # question_answer 76)   Identify the group and valency of the element having atomic number 119. Also predict the outermost electronic configuration and write the general formula of its oxide.

The present long form of periodic table has seven periods and the last element of this period is the element with atomic number 118. Thus, the element with atomic number 119 is the first member of 8th period and a member of alkali group with outer electronic configuration, $8{{s}^{1}}$. It belongs to first group and therefore, its valency is one. The formula of its oxide is${{M}_{2}}O$.