By atomic number.
atomic number Chemical elements are organized in the form of the periodic table of Mendeleev, in groups and periods.
- the periodic table is organized in periods and groups- chemical elements are listed in the order of the atomic number- the periodic table obey the law of periodicity
The rows in the periodic table are called periods. There are 7 periods in periodic table.
Periods have same shells. There are 7 periods in periodic table.
The periodic table has 7 periods on it.
rows. the vertical columns are called periods
Mendeleev's version of the Periodic Table was organized by increasing mass. The modern periodic table is now organized by atomic number.
The modern periodic table has seven periods.
The horizontal rows on the periodic table are periods.
Periods are horizontal rows. 7 periods are present in modern periodic table.
The horizontal rows are referred as periods. There are 7 periods in periodic table.
7The periodic table has 7 periods and 18 groups.