1. LEWIS STRUCTURES & MOLCULAR GEOMETRY

2. TYPES OF COVALENT BONDS SINGLE BONDS LONGEST OF THE 3 TYPES WEAKEST OF THE 3 TYPES CONTAINS ONE PAIR OF ELECTRONS (2 ELECTRONS) DOUBLE BONDS LENGTH IS GREATER THAN TRIPLE BUT LESS THAN SINGLE STRENGTH IS GREATER THAN SINGLE BUT LESS THAN TRIPLE CONTAINS TWO PAIRS OF ELECTRONS (4 ELECTRONS) TRIPLE BONDS SHORTEST OF THE 3 TYPES STRONGEST OF THE 3 TYPES CONTAINS THREE PAIRS OF ELECTRONS (6 ELECTRONS) LONGEST BONDS(SINGLE) ARE THE WEAKEST SHORTEST BONDS(TRIPLE) ARE THE STRONGEST

3. VSERP THEORY states that electron pairs found in the outer energy level or valence shell of atoms repel each other and thus position themselves as far apart as possible

5. FOR EXAMPLE, IN THE LEWIS STRUCTURE OF WATER, THERE ARE TWO NON- BONDED (LONE) PAIRS OF ELECTRONS ON THE OXYGEN ATOM. THUS THE NON-BONDED (LONE) PAIR OF ELECTRONS REPEL MORE THAN THE LONE- BONDED PAIR BETWEEN THE OXYGEN AND HYDROGEN AND THE BONDED- BONDED PAIR OF ELECTRONS BETWEEN THE TWO HYDROGENS HAVE THE LEAST REPULSION. NON-BONDED (LONE)& NON-BONDED (LONE) PAIR OF ELECTRONS NON-BONDED(LONE) & BONDED PAIR OF ELECTRONS BONDED- BONDED PAIR OF ELECTRONS

6. Due to the fact that lone pair of electrons repel more than bonded pairs, the bond angles will be different in different shaped molecules BEND(with 2 lone pair of e-) <TRIGONAL PYRAMIDAL<TETRAHEDRAL< BEND(with 1 lone pair of e-)<TRIGONAL PLANAR<LINEAR ****KNOW THE BOND ANGLES OF THIS SHAPES

7. LINEAR TRIGONAL PLANAR TETRAHEDRAL BENT (w/ 2 lone pairs of e-) TRIGONAL PYRAMIDAL.. S // \ :O:.. BENT (w/ 1 lone pairs of e-) 180 o 120 o 109.5 o 109.5 o (107.5 o ) 120 o (119 o ) 109.5 o (104.5 o )

8. ETHANOIC ACID CH 3 COOH 104.5 o TETRAHEDRAL TRIGONAL PLANAR BENT

9. CAN A MOLECULE BE NONPOLAR AND STILL HAVE POLAR BONDS WITHIN THE MOLECULE??? FIRST THINK ABOUT WHAT MAKES A BOND POLAR! NOW THINK ABOUT WHAT MAKES A MOLECULE NONPOLAR!

10. THE DIFFERENCE IN ELECTRONEGATIVITY VALUES (CHARGE SEPARATION) DETERMINE IF A BOND WILL BE POLAR OR NONPOLAR. 0-.3 difference is NONPOLAR.3-1.7 difference is POLAR IF A MOLECULE IS SYMMETRICAL OR IF THERE IS NO NET DIPOLE MOMENT THEN IT IS NONPOLAR EXAMPLE: CCl 4 THE C-Cl BOND IS POLAR BUT THE MOLECULE IS TETRAHEDRAL SO IT IS SYMMETRICAL AND THUS NONPOLAR YES

11. WHICH OF THE FOLLOWING BONDS IS THE MOST POLAR B-C or C-O or N-O or O-F ANSWER: C-O b/c they are further apart on the periodic table which means that they have the greatest charge separation.