Periodic Trends

Question 1

Atomic Radius

Answer 1

Definition: Distance from the nucleus of the outermost E- (VE)
* Down a group, atomic radius increases. (More E- are added to principle energy levels)
* Across a period, atomic radius decreases. (E- are added to the same energy level, pulling the E.L. tighter)

Question 2

Ionic Radius

Answer 2

Definition: Distance from the nucleus of the outermost E- (VE), one an atom has lost or gained an E-
* When an E- is lost, the radius decreases, for the electron pull is tighter.
* When an E- is gained, the radius increases, for the pull is weaker.

Question 3

Ionization Energy

Answer 3

Definition: Energy needed to remove an E- from an atom
* As the radius increases, the IE decreases, for the E- are farther from the nucleus & easier to remove.
* As the radius decreases, IE increases, for the E- are closer to the nucleus & harder to remove.

Question 4

Electronegativity

Answer 4

Definition: Love for E-
* As the radius increases, Eneg. decreases
* As the radius decreases, Eneg. increases.
* DOES NOT APPLY TO NOBLE GASSES