Chemical Bonding

Chemical Bonds When atoms of different elements combine to form compounds, the position of one or more electrons in the valence shell of each combining atom is altered. When such a shift in the location of electrons occurs, a force of attraction develops between the atoms involved. This force of attraction holds the two atoms together and is called a CHEMICAL BOND.

Chemical Reactions The formation and breaking of chemical bonds occur during chemical reactions.

Types of Chemical Bonds Ionic Bonds Covalent Bonds Metallic Bonds

Noble Gases The electron configuration of the noble gases are highly stable They all have a full octet – their outer electron shell is full Atoms all want to be stable They will either lose, gain, or share electrons to become stable

Ionic Bonding Occurs between a metal and a nonmetal Electrons from the valence shell of the metal will be transferred to the valence shell of the nonmetal Therefore, Metals lose electrons to achieve a stable octet Nonmetals gain electrons to achieve a stable octet

Na Cl Drawing Ionic Bonding 2 1 3 8 4 7 5 +1 6 -1 Draw each separate diagram 8 +1 -1

Naming Ionic Compounds When you name compounds, first name the cation then the anion Keep the cation the way it is Keep the first syllable of the anion and then change the rest to –ide Example: NaCl Sodium, Chlorine Sodium Chloride

Covalent Bonding Occurs between 2 non-metals Electrons are shared

Naming Covalent Bonds When you name covalent compounds you must following the rules: Write the name of the first element as it appears on the periodic table For the second element, keep the root word and add –ide to the end Example: oxygen = oxide Add prefixes to show how many there are of each element 1 – mono 2 – di 3 – tri 4 – tetra 5 – penta 6 - hexa H2O2 Dihydrogen dioxide