Atomic Structure and Periodic Table 1.3.3

Atomic Radius

Atomic Radius

Half the distance between the nuclei of two atoms of the same element joined by a single covalent bond

Across a period

Atomic radius gets smaller

Reasons ( across period )

Increasing nuclear charge, no increase in shielding affect

Down a group

Radius gets bigger

Reasons ( down a group )

New main energy level, decreasing effective nuclear charge

Trends in atomic and ionic size

Cations are smaller than parent atoms, anion are larger then parent atoms