Answer
For main group elements the row number is the highest principal quantum number in its electron configuration. For transition elements the principal quantum number is the row number minus 1. In inner transition elements it is the row number minus 2.
Work Step by Step
For main group elements the row number is the highest principal quantum number in its electron configuration. For transition elements the principal quantum number is the row number minus 1. In inner transition elements it is the row number minus 2.