Periodic Trends

Question 1

Ion Sizing

Answer 1

Cations are smaller than their parent atoms

Anions are larger than their parent atom

Inc down column
Dec across period

Question 2

Z effective

Answer 2

The net positive charge pulling e- towards the nucleus
higher the Zeff = e- closer to nucleus

As Zeff INCREASES, the size of the atoms DECREASES

Dec down a column
Zeff Inc across a period

Question 3

Atom Sizing

Answer 3

As valence electrons get farther and farther away from the nucleus, the atom gets smaller.

INC down a column
Dec across a period

Question 4

Ionization Energy (IE)

Answer 4

Down a group:
Valence increases
average distance from nucleus increases

Across a row:
Zeff increases

Exceptions:
groups 2&13
groups 15&16

Question 5

Electron Affinity

Answer 5

The energy released when an atom gains an electron to become an anion

Increases across
Decreases down

Question 6

Electronegativity

Answer 6

An atom’s tendency to attract e- towards itself in a covalent bond

Increases across
Decreases down

Fluorine is the most electronegative atom

Question 7

Dec across
Inc down

Answer 7

Atomic sizing / radii
Ion sizing

Question 8

Inc across
Dec down

Answer 8

Ionization Energy
Electron Affinity
Electronegativity
Zeff