Covalent Bonding

Covalent Bond Atoms are held together by SHARING electrons

Terms Molecule Neutral group of atoms joined together by covalent bonds Compounds

Diatomic Molecule Also Known As: The Magnificent Seven Molecule consisting two of the same atom Never exist by themselves Example: Oxygen (O2) Also Known As: The Magnificent Seven

Diatomic Molecules Nitrogen Oxygen Flourine Clorine Bromine Iiodine

Compounds Molecular Compound Ionic Compound Compound composed of molecules Collection of +ve and –ve charged ions repeating in a 3D pattern

Molecular Compound Lower melting and boiling points compared to ionic compounds Composed of two or more non-metals

Practice Worksheet: Identifying Ionic versus Molecular Compounds

Writing Formulas for Molecular Compounds

Binary Molecular Compounds Composed of two elements Metal and non-metal

H2O Molecular Formula Chemical formula of a molecular compound Example: Water H2O

Molecular Formula Represents the ACTUAL number of atoms in each molecule (NOT the lowest ratio) Example: Ethane C2H6

Naming Molecular Compounds

PreFixes Number Prefix 1 Mono- 2 Di- 3 Tri- 4 Tetra- 5 Penta- 6 Hexa- 7 Hepta- 8 Octa- 9 Nona- 10 Deca-

Rules: The name of a molecular compound indicates: # of atoms type of elements Prefix “mono” ONLY used on the second element For example: CO is carbon monoxide rather than carbon oxide.

Let’s Practice SO2 SF6 CCl4 NI3

More Practice… CF4 SiO2 SO3 P4S3

Practice Worksheet Naming Ionic and Covalent Bonds

The Nature of Covalent Bonding Grab a WHITEBOARD, MARKER AND TOWEL

The Nature of Covalent Bonding Electrons are shared so that each atom: gets eight electrons Or attains the noble gas configuration)

Hint The atom with the LEAST amount of valence electrons normally is in the middle… Exception: Hydrogen is ALWAYS on the outside Example: HOCl

Hint Sometimes the molecular formula tells you the arrangement of atoms Example: CH3COOH

Single Covalent Bond Two atoms held together by sharing ONE PAIR of electrons Pair of shared e- can be represented by a dash Structural formula Example: Hydrogen Molecule (H2) Water (H2O)

Unshared Pair Not shared between atoms Also known as: Lone Pair Non-Bonding Example: A fluorine molecule (F2)

Practice H2O2 PCl3

Practice Bromine Chlorine Iodine

Other Covalent Bonds Double Covalent Bond Triple Covalent Bond Atoms share two pairs of electrons Atoms share three pairs of electrons

Double and Triple Bonds

Double and Triple Bonds C2H6O NH3

Try These… CO CF4

Coordinate Covalent Bonds

Coordinate Covalent Bond A covalent bond in which one atom contributes BOTH bonding electrons Example: CO2

Coordinate Covalent Bonding SO3 ClO3

Try this one… NH4

Drawing Polyatomic Ions REVIEW: A tightly bound group of covalently bonded atoms that have a positive or negative charge and behave as a unit Example: [SO3]2-

Polyatomic ions Contain both covalent and coordinate covalent bonds Electronegativity: The ability of an atom to attract electrons when the atom is in a compound More electronegative elements will GAIN electrons Less electronegative elements will LOSE electrons [OH]-

Practice [BF4]- [SO4]2- [CO3]2-

Practice Problems [BF4]-

Practice Problems [SO4]2-

Practice Problems [CO3]2-

Bonding Videos… Ionic vs. Covalent Bonding