They have the same number of electron shells.
Rows in the Periodic Table are called Periods.There are 7 periods in total.All the elements in period have same number of energy levels.
Periods have same shells. There are 7 periods in periodic table.
These are the periods 4 and 5.
Blood.
Elements in the same period has same number of valence shells.There are 7 periods in Periodic Table.
The rows going across the periodic table are known as periods and contain elements with the same number of electron shells.
Modern periodic table has 7 periods and 18 groups.
Periodic table is arranged by atomic number. elements are arranged in groups and periods.
Horizontal rows of elements in the periodic table are called periods. Each period represents a different energy level, with elements in the same period having the same number of electron shells. Periods are arranged in numerical order from left to right on the periodic table.
Period 4 and period 5 of the periodic table have the same number of elements. There are 18 elements in each period. While some elements in period 4 are calcium, iron, and zinc, elements in period 5 are tin, antimony, and iodine.
The elements in a given period have the same number of core electrons.
Rows are called periods. They contain same number of shells.