Chemistry 112Sections 4-6

Bill Vining232 PSCI436-2698

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 week- they start Monday

• Class Rules- Syllabus (go over on Friday)

Business II

• 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

Classroom Rules

Business III

• 3 Hour Exams

• OWL Homework

• Labs

Grades

Business IV

If I fail the lab,

Recite After Me:

I fail the course.

Mastery Learning Schematic

Homework Question

Correct Answer and Feedback

Answer

Mastery Credit

Newly generated question

correct

incorrect

Mastery Learning Schematic

Homework Question

Correct Answer and Feedback

Answer

Mastery Credit

Newly generated question

correct

incorrect

Guided Tutorial

Concept Simulation

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 Assignment #3

Unit #1

Unit #2

Unit #1

Unit #2

Unit #1

Assignment Scheme III: Units have Questions

Course

Assignment #1 Assignment #2 Assignment #3

Question #1Question #2

Unit #1

Question #1Question #2

Unit #2

Question #1Question #2

Unit #1

Question #1Unit #2

Question #1Question #2Question #3Question #4Question #5

Unit #1

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 Covalent

Electrons Shared More Equally

Bonding

When atoms stick together, that’s bonding.

Bonding ranges from ionic to covalent:

Ionic Polar Covalent Covalentmetals+nonmetals different nonmetals similar nonmetals

Electrons Shared More Equally

Why do Covalent Bonds Happen?

Why do Covalent Bonds Happen?

Electrons on oneatom attracted tonucleus 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 Lewis Electron-Pair Molecular

Electrons Structure 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. Linear

2. Bent 109o

3. Trigonal planar

4. Trigonal pyramidal

5. Tetrahedral

6. Trigonal bipyramidal

7. See-saw

8. Square pyramidal

9. 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