Chemistry 112 Sections 4-6 Bill Vining 232 PSCI 436-2698 viningwj@oneonta.edu You should have had: • General Chemistry I – Up through drawing Lewis Structures General Chemistry I • • • • • • • • • Basics of Atomic Structure Chemical Reactions and Equations Stoichiometry Solution Chemistry, mainly in water Thermochemistry Electronic Structure of Atoms Properties of Atoms Ionic Bonding Covalent Bonding of p-Block Elements General Chemistry II • Molecular Structure • Bonding Theories – Valence Bond Theory – Molecular Orbital Theory • Properties of Gases • Control of Chemical Reactions and Stability – Thermodynamics – Kinetics General Chemistry II • Special Types of Chemical Systems: – Organic – Equilibrium – Acid-Base – Dissolution – Complexation – Electrochemical Business Class Rules • Syllabus • Class Rules: – Be here every day – Be on time – Pick up handouts if late – No chatting, except when I say so – You are responsible – Be nice – Trust me Business I • Class meetings: – Lecture MWF here – Lab once a week in Physical Sciences Bldg. – Recitation once a week in Physical Sci. Bldg. • NO LABS or RECITATIONS this weekthey start Monday • Class Rules- Syllabus (go over on Friday) Business II Classroom Rules • • • • • • Be here every single day Be here on time Don’t sit in back Don’t talk when I’m talking Don’t let me talk when you’re talking It’s ok to get up and wander Business III Grades • 3 Hour Exams • OWL Homework • Labs Business IV Recite After Me: If I fail the lab, I fail the course. Mastery Learning Schematic Homework Question Answer Correct Answer and Feedback correct Mastery Credit Newly generated question incorrect Mastery Learning Schematic Concept Simulation Homework Question Guided Tutorial Answer Correct Answer and Feedback correct Mastery Credit Newly generated question incorrect Tutorial Help Tutorial Help Concept Simulations Assignment Scheme I: A course has Assignments Course Assignment #1 Assignment #2 Assignment #3 Assignment Scheme II: Assignments have Units Course Assignment #1 Assignment #2 Unit #1 Unit #1 Unit #2 Unit #2 Assignment #3 Unit #1 Assignment Scheme III: Units have Questions Course Assignment #1 Unit #1 Question #1 Question #2 Unit #2 Question #1 Question #2 Assignment #2 Unit #1 Question #1 Question #2 Unit #2 Question #1 Assignment #3 Unit #1 Question #1 Question #2 Question #3 Question #4 Question #5 Bonding When atoms stick together, that’s bonding. Bonding ranges from ionic to covalent: Bonding When atoms stick together, that’s bonding. Bonding ranges from ionic to covalent: Ionic Polar Covalent Electrons Shared More Equally Covalent Bonding When atoms stick together, that’s bonding. Bonding ranges from ionic to covalent: Ionic metals+nonmetals Polar Covalent Covalent different nonmetals similar nonmetals Electrons Shared More Equally Why do Covalent Bonds Happen? Why do Covalent Bonds Happen? Electrons on one atom attracted to nucleus of other atom Nucleus on each atom repels other nucleus Electron on each atom repels other electron If new attractions > new repulsions, then a bond forms How Covalent Bonds Happen Valence electrons are shared through overlapping orbitals Covalent Bonding in p-Block Elements: Where are the Valence Electrons? Covalent Bonding in p-Block Elements: Where are the Valence Electrons? • Described by Lewis Electron Dot Structures Determining Molecular Geometry • All depends on bond angles: Determining Molecular Geometry • All depends on bond angles: Determining Molecular Geometry Valence Electrons Lewis Structure Electron-Pair Molecular Geometry Geometry Electron-Pair Geometries • Depend on Number of Electron Pairs around Central Atom Help Needed • Today – Lunch 12-12:50 – Lecture 3:30 – 4:15 • Tomorrow – Lunch 12-12:50 – Lecture 3:30 – 4:15 Examples NH3 CH4 CH2O 1. 2. 3. 4. 5. 6. 7. 8. 9. Linear Bent 109o Trigonal planar Trigonal pyramidal Tetrahedral Trigonal bipyramidal See-saw Square pyramidal Octahedral Molecular Polarity Are electrons in molecules evenly distributed? If so: nonpolar molecule If not: polar molecule Determining Bond Polarity Compare electronegativities of bonded atoms Determining Bond Polarity Compare electronegativities of bonded atoms H-F is: Li-F is: N-O is: O-O is: P-H is: Determining Molecular Polarity Add up all bond polarities and see if they cancel Polarity Examples