Core Periodicity IV: Physical Properties

Core Periodicity: Physical Properties

Slide 7 of 35

Trend and explanation

Just as ionization energy, size of atom also depends on the nuclear charge and the number of shells it contains.

As already noted, going across a period, the nuclear charge increases while the number of shells remain the same.

Overall, the attractive force increases and causing the atomic radius to decrease.

–The bigger nuclear charge pulls the electrons closer towards itself.

Going down a group the size increases since the number of shells increases.

–The valence electrons are found at a farther and farther distance from the nucleus.

So, in general, between atoms containing the same number of shells, the one with the greater nuclear charge will be smaller, while between atoms containing different number of shells, the one with the smaller number of shells will be smaller.