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The modern periodic table has seven periods.
The periodic table has 18 groups ant 7 periods. Hydrogen and helium are considered members of the first period.
There are seven periods on the periodic table. The lanthanides are in period 6, and the actinides are in period 7.
There are 7 periods in the modern periodic table.
The Periodic Table has 18 groups and 7 periods.
Periods are the horizontal rows in the periodic table of Mendeleev; this table contain 7 periods.
Horizontal rows are termed as periods. There are 7 periods in periodic table.
There are 7 periods in the modern periodic table.
7 periods and 18 groups are there on the modern periodic table.
The Periodic Table has 7 periods (horizontal rows) and 18 groups. The two groups of 14 elements at the bottom (lanthanides and actinides) are parts of the 6th and 7th periods, between groups 2 and 3, but are placed below to limit the displayed width of the table.
Th horizontal rows are referred as periods. There are 7 periods in Periodic Table.
7 periods and 18 groups are there on the modern periodic table.