Lectures
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Provide a “big picture”
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Lecture Syllabus
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How do we think about “science”?
How do we solve a problem?
Page 8 of Lab Book
Interactive
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I expect and encourage questions.
Participation expected through clickers.
Let’s Give it a Try…
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Astronauts undergo some of the most rigorous training
ever conceived. They must be able to perform
dangerous work while hurtling through space, all
without throwing up. China is after only the best of the
best for its space program, so candidates are tested for
what?
A) Hand-eye coordination
B) Bad breath
C) Sobriety
D) Parallel parking skills
Source: Wait Wait…Don’t Tell Me! Daily News Quiz, 8/6/09
Answer
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The correct answer is B. If you want to become a
Chinese astronaut, don’t forget to floss; the Chinese
training program won’t accept space hopefuls who
have bad breath.
Ever ready to meet the needs of the marketplace,
Altoids quickly responded with a new product line:
Asteroids: The Curiously Strong, Suborbital Mint.
Source: Wait Wait…Don’t Tell Me! Daily News Quiz, 8/6/09
Clicker Points
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Participation Points – answer at least 75% of
the questions per lecture
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1 point per lecture
Capped at 20 points (24 lectures w/ clickers)
Bonus Points – earn 0.2 points for every
question you answer correctly
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Not to exceed 1 point per lecture
Friday Sections
Smaller groups, more details in
solving problems.
 You must take an active role.
 Ch. 2 and 3 HW due tomorrow
(p. 10 of Lab Book)
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Electronic Homework
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www.chem.illinois.edu (course website)
Follow “Lon-Capa Access Instructions”
HW #1, Type 1: due Tues, 9/4, 7:00 pm
HW #1, Type 2: due Wed, 9/5, 7:00pm
Receive no credit after due date.
Individualized assignments.
Video Hints and Tutorials
Can Post Discussion
Electronic Homework
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Type 1 Homework
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99 tries
Usually due Mondays (deadlines posted
next to each actual assignment)
Type 2 Homework
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5 tries
Usually due Wednesdays (deadlines posted
next to each actual assignment)
Chemistry 101
How did lab go with your TA?
 Must have usage fee card by
next week’s lab.
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Lab Sections
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Lab write-ups must consist
of coherent explanations
and complete sentences.
This is another chance for
discussion of chemical
principles.
Exams
Evening exams (7-8:15 pm).
Dates given in the Lab Book.
 Multiple choice and free
response.
 Emphasis on understanding.
 Previous exams given in the Lab
Book.
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Chemistry 101
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Slower pace after next week
Office hours – 105 Chem Annex
9-10 am Tuesdays and Thursdays
 By appointment
 [email protected]
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Chemistry 101
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212 Chem Annex
Walk in tutors
 Office hours
 Reference materials
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General Email Advice…
To: [email protected]
From: [email protected]
I dont get problem 3
Srsly, plz help thx
~J
Email Advice
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Put CHEM 101 in the subject
Acknowledge instructor’s name.
Put your name.
Use @illinois email account if possible.
(otherwise put netid after name)
Do not use “text message” code.
Put your section.
Do not erase the message I sent
previously (the email record).
To: [email protected]
From: [email protected]
Subject: CHEM 101 Lab Book problem
Hi Stacie,
I am having trouble understanding problem #3
of the Additional Questions on pg. 23 of the
Lab Book. How am I supposed to make my
drawings for each measurement? Can you
please give me some guidance? Thanks!
-Jane (jdoe25, ADM, Chem 101)
Chemistry and Reactions
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Chemistry is the study of matter
and its changes.
Will focus heavily on chemical
reactions
 To explain, predict and understand
those reactions we need ways of
thinking about those reactions
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Unknown Clear Liquid
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Why do things have smell or
taste?
Dissolving Sugar in Water
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Can still taste the
sugar, where did
the sugar crystals
go?
What does
“dissolve” mean?
Particulate Theory of Matter
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To understand chemical reactions, we
have to think about what reactions are
composed of
“particles” (Particulate Theory of Matter)
Helps to explain our observations (smell
of vinegar, taste of sugar)
Thus, there must be “pieces” of vinegar
and water (acting as units)
Chemistry and Reactions
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Chemistry is the study of matter
and its changes.
Will focus heavily on chemical
reactions
 To explain, predict and understand
those reactions we need ways of
thinking about those reactions
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Demo: Electrolysis of Water
Compounds
Elements
Particulate Nature of Matter
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Atom: smallest part of an element
that is still that element
(fundamental unit of which
elements are composed).
Molecule: Two or more atoms
joined and acting as a unit.
(element or compound)
Particulate Nature of Matter
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There is a similarity between the
atoms of various elements and the
alphabet. We can make thousands
of words based on 26 letters of the
alphabet. Similarly, millions of
compounds can be made by using
these 100 or so elements.
Atomic
Element:
single
atom of
that
element
Molecular Elements:
molecules of the same
element
Compounds: composed of the
atoms of 2 or more elements
Clicker Question
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How many of the following are
compounds?
S8, NO2, KCl, CH4, H2SO4
A)
B)
C)
D)
E)
1
2
3
4
5
Clicker Question
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How many of the following are
compounds?
S8, NO2, KCl, CH4, H2SO4
A)
B)
C)
D)
E)
1
2
3
4
5
States of Matter
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Knowledge of the states of matter are
important to understanding chemical
reactions and changes as well
Knowing what a substance looks like
microscopically can help us understand why a
substance looks the way it does
macroscopically (especially when a chemical
reaction occurs)
Macroscopic versus Microscopic
more ordered
less ordered
very disordered
Physical Change
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A change in one or more physical
properties, but no change in the
fundamental components.
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Changes of State
Macroscopic versus Microscopic
H2O
H2O
H2O
Chemical Change
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A change in the fundamental
components of the substance.
Create something new/different
 Chemical changes are called
reactions.
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Chemical Reaction
Chemical Equations
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Law of Conservation of Matter (will
discuss in detail later)
Clicker Question
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How many of the following are examples of a chemical
change?
I.
burning of wood
II.
pulverizing (crushing) rock salt
III.
dissolving of sugar in water
IV.
melting a popsicle on a warm summer day
A)
B)
C)
D)
E)
0
1
2
3
4
Clicker Question

How many of the following are examples of a chemical
change?
I.
burning of wood
II.
pulverizing (crushing) rock salt
III.
dissolving of sugar in water
IV.
melting a popsicle on a warm summer day
A)
B)
C)
D)
E)
0
1
2
3
4
Mixtures
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Pure substance – constant
composition (elements or
compounds)
Two or more pure substances
remaining independent of each
other – mixture
Example: sugar water
Types of Mixtures
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Homogeneous mixtures → same
throughout; no matter what part you
take, it’s the same sugar water
2) heterogeneous mixtures → has
different properties from those of other
regions (oil/vinegar dressing; milk if not
homogenized)
DISCUSS
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What about the air in this
classroom?
homogeneous or heterogeneous?
DISCUSS
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What about the air in this
classroom?
homogeneous or heterogeneous?
Always ~80% N2, ~20% O2
Always a 4:1 ratio!
Clicker Question
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Which of the following is a homogeneous
mixture?
A) potting soil
B) sodium chloride (table salt)
C) pure water
D) oil and vinegar dressing
E) sports drink (like Gatorade)
Clicker Question
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Which of the following is a homogeneous
mixture?
A) potting soil
B) sodium chloride (table salt)
C) pure water
D) oil and vinegar dressing
E) sports drink (like Gatorade)
Don’t Forget!
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Chapter 2 and 3 textbook problems
are due in discussion section
tomorrow!
HW#1 Type 1 is due Tuesday at
7pm and HW#1 Type 2 is due by
Wednesday at 7pm