Bonding… what the force?

RECAP: Chemical Bond The forces that hold groups of atoms together and make them function as a unit Bonding involves only the valence electrons There are 2 types of bonds: Ionic: Transfer of electrons from a metal and to a nonmetal Covalent: Sharing of electrons between 2 nonmetals Note: When 2 metals bond an alloy is formed Electrons are transferred or shared to give each atom a noble gas configuration (stable octet) This is known as the octet rule

Ionic Bonding

Ionic Bonding Metals Nonmetals Electron donors Donate their valence electrons to become a positive ion (cation) Nonmetals Electron acceptors Accept valence electrons to become a negative ion (anion)

Ionic Bonding

Ionic Bonding The two oppositely charged ions are attracted to each other by a force called an ionic bond

NaCl Crystal Lattice Ionic compounds form solids at SATP. Ionic compounds organize in a characteristic crystal lattice of alternating positive and negative ions. All lattices are arranged so that each ion has the greatest possible number of oppositely charged ions close by, while keeping similarly charged ions as far away as possible

Properties of Ionic Compounds Structure: Crystalline solids Melting point: Generally high Boiling Point: Electrical Conductivity: Excellent conductors, molten and aqueous Solubility in water: Generally soluble

Covalent Bonding

Covalent Bonding Between 2 Nonmetals Share the available electrons

Properties of Covalent Compounds Structure: solid, liquid or gas Melting point: Usually low Boiling Point: Electrical Conductivity: Does not conduct Solubility in water: usually insoluble