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Groups and periods are two ways ofcategorizing elements on the periodic table.Periods are horizontal rows (across) theperiodic table, while groups are vertical columns (down) the table. Atomic number increases both as you move down a group or across a period.
Group and period are two ways of categorising the periodic table. The group are arranged horizontally (across), while the period are arranged vertically (down) the table. Atomic number increases both as you move down a group or across a period. Atomic number increases both as u move down a group or across a period