Question

What is the trend of the following when you move from top to bottom?

Atomic radius
Atomic size
Ionization energy
Electron affinity
Electronegativity
Metallic character

Answer 1

The trend when moving from top to bottom in the periodic table shows increasing atomic radius and metallic character, and decreasing ionization energy, electronegativity, and electron affinity, influenced by the number of protons, electron shells, and shielding effect.

Step-by-step explanation:

Trends in the Periodic Table

When moving from the top to the bottom of the periodic table, several trends can be observed:

1. The atomic radius and atomic size tend to increase. This is because with each lower element in a group, a new electron shell is added, which means the valence electrons are in a higher shell and are further from the nucleus.
2. Ionization energy tends to decrease. This is because the added shells cause the valence electrons to be further from the nucleus, reducing the energy required to remove an electron.
3. The trend in electron affinity is less regular, but generally, electron affinity becomes less negative as we move down a group due to the added distance between the nucleus and the valence electron shells.
4. Electronegativity generally decreases as one moves down a group, since the increasing distance between the valence electrons and the nucleus makes the atoms less able to attract bonding electrons.
5. The metallic character increases moving down a group as the ease of losing electrons (a metallic property) increases due to the greater distance of the valence electrons from the nucleus.

Three main factors predict these trends: the number of protons in the nucleus, the number of electron shells, and the shielding effect caused by inner layers of electrons.