Ionic and Covalent Bonding Ionic Transfer Covalent Share

What holds bonded atoms together? Bond when valence electrons interact The (+) nucleus of one atom attracts the (-) ion from another like magnets

Bonds can bend and stretch Bonds are not really rigid, like the stick in ball and stick models They act more like springs.

Ionic bonds are a transfer of electrons Ionic Bonds have positively charged ions attracted to negatively charged ion. Cations (+) are positive, metals CAT PAWS CATions are PAWsitive *Anions (-) are negative, non-metals Metal + Non-Metal have ionic bonds and are therefore call Ionic Compounds

Ionic Compounds Are in the form of network solids They are neutral Each (+) and (-) ion form a formula unit

Characteristics of Ionic Compounds High Melting points Strong Bonds Brittle Dissolve in water Solid states do not conduct electricity Liquid state does conduct electricity

Metallic Bonds Conduct Electricity Flexible Ductile Malleable “Sea” of electrons formed

Covalent Bonding A covalent bond is formed by a shared pair of electrons between two atoms.

Molecules Share more than 1 pair of electrons Bonds may be….. Single- 1 shared electron pair represented by 1 line. Requires some energy to break Double- 2 shared electron pair represented by 2 lines. Requires more energy to break Triple-3 shared electron pair represented by 3 lines. Requires the most energy to break

Polarity Polar means two opposite ends Not all electron pairs are shared the same They are attracted to one nucleus more than the other This is a polar covalent bond

Ionic Compounds Polyatomic ions Poly- means many or more than one These are two or more atoms bonded together with an overall charge Most polyatomic ions are negative Parentheses will group polyatomics in a compound Mg(NO3)2 An –ate ending means there is an oxygen atom involved in the polyatomic ion