the atomic number.
groupsi
The energy of the valence shell remains the same.
A row of elements across the periodic table is called a period. Periods represent the number of electron shells in an atom.
Period
A horizontal row on the periodic table of elements is called a period.
Across a period, as we move from left to right, the electronegativity increases in the periodic table.
Atomic size decreases across a period
The periodic table is an arrangement of the elementsfound in nature.
The atomic number increases
period 4, 11 across
Periods (across the Periodic Table) have increasing Atomic Mass. Groups (down the table) have similar properties and reactive natures.
its called a period.