Ionic BondsChapter 8, Section 1

Vocabulary Anion Cation Chemical bon Formula unit Ionic bond Lattice energy Monatomic ion Oxidation number Polyatomic ion

Alloy Delocalized electrons Electrolyte Electron sea model Metallic bond Oxyanion

Ionic Compounds What are

Chemical Bonds

Force that holds 2 atoms together

Attraction between + nucleus and – electron

Attraction between + ion and – ion

Valence electrons make bonds

Ionic compounds What

are chemical bonds? (cont)

Elements react to form a stable octet (noble gas configuration). The + and – charges act like opposite

poles of a magnet. Opposites attract strongly Likes repel strongly Strength diminishes with distance

Ionic Compounds

How are positive ions formed?

Atom loses one or more VALENCE electrons

Called a CATION Ion becomes more stable by losing

electrons (octet rule) Not a change in atom, Just an ion Loses all electrons in outer shell

Reactivity depends on ease of losing electrons

Transition metals usually form 2+ or 3+ ions shown with a (II) or (III)

Ionic Compounds How are

positive ions formed?

Group 1A loses 1 valence electron Group 2A loses 2 valence electrons Group 3A (13) loses 3 valence

electrons Group 4A (14) does not generally

make ionic compounds

Ionic Bonds How are

positive ions formed ? (Cont)

Transition metals give up the 4s electrons to make pseudo-noble gasses

Ionic Bonds How do

negative ions form?

Atoms gain negative electrons Nonmetals have a great attraction for

electrons Adding electron fills up the shell = stable

Called an ANION Naming: change name to end in –ide Gaining enough electrons to fill outer

shell (octet rule) 7A gains 1 6A gains 2 5A gains 3

Ionic Compounds Ionic compounds are Metal+ and Nonmetal- Metals make Cations

Groups 1A (1) – 3A (13) and all Group D elements Form + ions

Nonmetals make Anions Group 5A (15) - 7A (17)

Nobel Gasses (Group 8A/18) do not form compounds. Why?