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