UNIT 1.7 PERIODIC TRENDS

Chemistry is the study of matter and interactions. Chemistry overlaps with many other sciences.

Below is the contents for this sub unit. If you have taken Chemistry 1, this should all be review but it is always good to brush up on the basics (significant figures especially).

PERIODIC TRENDS

Review History of the atom for introduction of periodic trends

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There are multiple trends:

Size of the atoms (increase towards bottom left of periodic table)

Electronegativity (increase towards top right of periodic table)

Electron Affinity (increase towards top right of periodic table)

Ionization energy (increase towards top right of periodic table)

Small exceptions to these rules will be covered, such as a half filled p or d orbital can give a small step in the trends

But Families are a trend as well:

Group 1 elements react easily (throw most in water and they release so much energy they start a fire)

Hologens - all reactive with group 1.

Noble Gases - not reactive at all

All of these trends are based on the arrangement of atoms on the periodic table and how the valence electrons of those atoms are similar.