Three types of bonding

•  ionic
• covalent
• metallic

• the attraction between two oppositely  charged ions

Sodium  and Chorine      Na+ (loses an electron)  Cl- (gains an electron)      NaCl (electrically neutral together)

Naming Ionic Compounds
    The positively charged ion is named first
    The negatively charged ion changes it's name to "ide"

• NaCl  Sodium and Chlorine  becomes Sodium Chloride

• MgO   Magnesium and Oxygen becomes Magnesium Oxide

                    CO₃^-2   carbonate ion

                    CaCo₃   calcium cabonate

Naming Polyatomic Ions
    The positively charged ion is named first
    The negatively charged ion changes it's name to "ate"

            NaHCO₃

           Sodium Bicarbonate
 
Properties of Ionic Bonds
 

Crystal shape  the negative ion and positive ion fit together    repeating pattern to form the crystal lattice or structure

 
 
 

Electrical conductivity   dissolved in water            slide past each other              solution conducts electricity             flow of electric charges     high temperature (melting of ionic compounds)           produces the same result of electrical flow

 

Covalent Bonding

    co= with or together
    valence = electron(s) on the outermost energy level
    electron sharing
       -  chemical bond formed

          Oxygen + Oxygen     O::O  or     O₂

How many bonds

• single bond

• double bond

• triple bond

Properties of Molecular Compounds

• lower boiling points than ionic bonds
• poor conductors of electricity

• difference leads to different properties in polar and nonpolar compounds

                nonpolar - do not dissolve well in water
                    (i.e.  oil)

Sharing of electrons
 

Picture:Beyonds books

polar      some atoms pull more on the electrons than others  H : Br      -->  Properties of Polar Bonds       crystalline shape       high melting point -solid at room temperature       electrical conductivity

 
 

nonpolar  equal pull between atoms  H : H <---   --->

 

Metallic Bonding

• Alloy

              Generally stronger

              Less reactive

Properties of Alloys

Physical  retains many properties of metals

Chemical  Keeps metal from corroding

 

• Metals

Combine in regular patterns valence electrons are free to move from atom to atom                  "sea of electrons"

•  Metallic Properties

                Ductility

                Luster

                High electrical conductivity

                High thermal conductivity of solid metals.