They all have a filled 1s orbital
earths crust , oceans and atmosphere
Elements in the same group have more in common because they have the same number of valence electrons, leading to similar chemical properties. Elements in the same period have increasing atomic numbers and electron shells, but their properties can vary widely due to different numbers of electron shells and arrangements.
The elements on the periodic table are separated into periods based on the number of electron shells they have. Elements in the same period have the same number of electron shells, which influences their chemical properties and reactivity.
There are 18 periods in the periodic table. The periods are divided according to the chemical properties of elements. Elements in a group have similar properties.
Elements of same row has equal number of shells.
The early periods have less elements because they are filling up energy levels which hold only a few electrons. The later periods contain elements with electrons in levels with a greater capacity.
there are 32 elements in period 6.
There are 18 elements in period 4.
The relationship between elements and periods according to the periodic law is that elements are arranged in periods based on their atomic number and properties. Elements in the same period have the same number of electron shells, while elements in the same group have similar chemical properties.
Horizontal rows are called periods. There are 7 periods in periodic table.
The periodic table of Mendeleev has 18 groups and 7 periods.
These are the periods 4 and 5.