Chapter 6 2 Ions and Charges Groups vertical

Chapter 6. 2 Ions and Charges

• Groups: vertical – Determine behavior • Periods: horizontal – Energy level Think-Pair-Share Why does the group number determine the behavior of an element and not period number? (Hint: think about valence electrons and the octet rule)

Draw your answer

Lewis Dot Structures -Only draw valence electrons -4 groups of two -4 single electrons, then pair them up.

Valence electrons • Valence Electrons – Electrons that determine behavior – electrons used in bonding elements – Electrons in the highest (outermost) energy level • s and p sublevels – maximum is 8 • Why do s and p determine valence electrons?

Valence Electrons • Bromine’s Electron Configuration # of electrons in that energy level 1 s 2 2 p 6 3 s 2 3 p 6 4 s 2 3 d 10 4 p 5 Group 7 A 7 valence electrons Highest Energy level The d orbital will always be one lower than s and p. Therefore, s and p have the valence electrons.

Ions • Atoms gain or lose electrons to obtain a noble gas configuration (magic # 8) – Cations: positive charge bc they LOSE electrons. • Ca: loses 2 e- becomes +2 charge to be like Ar (Ca+2) – Anions: negative charge bc they GAIN electrons • Cl: gains 1 e- becomes -1 charge to be like Ar (Cl-)

Group Practice • Predict what the charges of the following elements will be after they have become ions. 1. Li, Be, Ca, F 2. Na, K, Ra, Te 3. Ga, Tl, Al, S 4. N, Cl, Po, Cs 5. Ba, B, P, As 6. H, He, N, O 7. Mg, Sr, In, I When you’re done, have 1 person come up to the board and draw your answers using Lewis Dot Structures.

Charges of the Ions