welcome to chemistry 102 - university of...

Welcome to Chemistry 102

Who, What and Where?

• Instructor: • Office and Office Hours

• Email:

What Do You Need?

• Textbook

– Chemistry, Zumdahl, 9th Ed.

• iClicker

– To register, go to iclicker.illinois.edu

– Follow the instruction

– Use your netID

Where Can I Find Things?

• For course policy, lecture schedules,

• Our course website

• http://www.chem.illinois.edu

• For online homework and

online quizzes – LON-CAPA

• See also FAQs section in the course policy

Grading Guidelines

Online Homework (LON-CAPA) 75

Clicker Points (in class) 25

Quizzes (LON-CAPA - 100 pts and

discussion – 50 pts) 150

Hourly Exams (150 pts each x 3) 450

Final Exam 300

Total 1000

A = 900 – 1000

B = 800 – 899

C = 700 – 799

D = 600 – 699

F = < 599

Hourly Exams and Final

Hourly Exams (7:00 – 8:15 pm, location TBA)

• 1st – Tuesday, 9/24

• 2nd – Thursday, 10/24

• 3rd – Thursday, 11/21

Final Exam

• There will be NO MAKEUP

exams or final

Discussion Section

• Purpose of discussion

– reinforce lecture material, develop problem solving skills

– TA’s role – to help and facilitate the learning process

– DO NOT ask your TA to just give you the answer!

• Can access the weekly worksheet on Lon-CAPA

• Purpose of lecture

– Review material,

– learn new concepts, and

– provide explanation

Don’t Despair!!

• There is help available – Instructor

– Chemistry Learning Center

– TAs

Some Word of Advice

• Learning chemistry is not a “spectator” sport!

• Practice, Practice, Practice

• Do something everyday

• Quality study time

Measurement Basics

• Unit of Measurement – SI (Systeme International)

Mass kilogram kg Length meter m Time second s Temperature kelvin k Elect Current ampere A Amt of sub. mole mol Luminous int. candela cd

Uncertainty and Significant Figures

• Why worry about sig figs

– Gives us the uncertainty of your measurement

Precision vs. Accuracy

Uncertainty and Significant Figures

• Sig figs rules – Nonzero integers always count as sig figs.

– Zeros

1. Leading zeros (zeros that precede the nonzero digits) do not count as sig figs

2. Captive zeros (zero btw nonzero digits), these count as significant zeros

3. Trailing zeros (zero at the right end of the number), only counts if there is a decimal.

Exact numbers - infinite # of sig figs

Significant Figures in Math Operations

• Addition and subtraction

• Multiplication and division

Significant Figures (cont’d)

• What about mixed operations?

Unit Conversions

Mass

Length

Temperature

Unit Conversions Example

You need to build a square vessel to contain 5.00 gallons of water, what would the dimensions of the square container in centimeters? In meters?

Density

If you have 100. ml of each three liquid,

Which one would be the lightest?

(= mass/volume)

Ethanol (100%) = 0.789 g/mL

mercury = 13.6 g/mL 1.00 g/mL

For Discussion on Wed. 8/28/13

• Worksheet #1

• Review Sig Fig Rules

• Brush up on unit conversion, density calculations