chapter 1 the chemical world - montclair state universitywhitener/courses/sp2011/... · chapter 1...
TRANSCRIPT
Roy Kennedy
Massachusetts Bay Community College
Wellesley Hills, MA
Introductory Chemistry, 3rd Edition
Nivaldo Tro
2009, Prentice Hall
Chapter 1
The Chemical
World
Figure 1.1 showing a
soda, a student writing.
The structures of atoms
and molecules are also
shown including the
components of the soda,
the student’s DNA, and
graphite in the pencil.
Outline
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1.1 Soda Pop Fizz
1.2 Chemicals Compose Ordinary Things
1.3 All Things are Made of Atoms and Molecules
1.4 The Scientific Method: How Chemist Think
1.5 A Beginning Chemist: How to Succeed
1.1 Soda Pop Fizz
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Chemistry at a Study Session
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Figure 1.1 was blown up here.
Some molecules in the soda:
Sugar
Carbon dioxide
Water
Caffeine
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What is Chemistry?
• Science
• Matter
• Change
• Heat
• Macroscopic
• Microscopic
The molecular models for
Carbon dioxide CO2 and
water, H2O are shown here
From page 2 of the text.
1.2 Chemicals Compose
Ordinary Things
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Chemicals
• Chemicals = ?
• Present in ordinary substances.
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1.3 All Things are Made of
Atoms and Molecules
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“All things are made of atoms”
• Richard Feynman photo at Wikipedia.
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Nobel Prize winning scientist and famous physics teacher
Richard Feymman said this is the most important idea
in human knowledge.
Your text’s definition of chemistry:
Chemistry – The science that seeks to understand
what matter does by studying what atoms and
molecules do.
1.4 The Scientific Method:
How Chemist Think
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Scientific Method
Figure 1.2 which shows a flow chart of the connections
between the steps in the scientific method.
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The Scientific Method
• Observation
• Hypotheses
• Experimentation
• Laws
• Theories
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Observation• Data.
• Qualitative
• Quantitative The Figure here is the cover page that
Is before page one of the text that
Shows the soda being poured into a
glass
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Hypothesis
• A good hypothesis is one that can be tested to
be proven wrong.
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Experiments
• Tests of hypotheses, laws, or theories.
• Results either validate (confirm) or invalidate (deny) your ideas.
Validate ≠ Proof your idea will always hold
Invalidate = Discard or Modify.
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Laws
• Summary of observations that combines all
past observations into one general statement.
Law of Conservation of Mass— “In a chemical
reaction matter is neither created nor destroyed.”
My definition from class – In a chemical reaction
the mass of all materials at the start of the reaction
is equal to the mass of all material at the end of
the reaction.
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What’s the Difference Between an
Observation and a Law?
• An observation - a single event.
• A law summarizes many observations.
• A law allows prediction.
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Theories
• General explanation that has been tested by
experiments.
• Models of nature.
Dalton’s Atomic Theory
• Can be used to predict future observations.
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What’s the Difference Between a
Hypothesis and a Theory?
• A hypothesis - a single or small number of
observations.
• A theory – extends beyond individual
observations to an understanding of the
underlying causes for the way nature is or
behaves.
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What’s the Difference Between a
Law and a Theory?
• Laws answer the question “What” will
happen.
• Theories answer the question “Why” does
something happen.
This allows you to predict what will happen!
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Scientific Method
Representation of Figure 1.2 with definitions of the
steps in the scientific method.
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Relationships Between Pieces of the
Scientific Method
• A figure describing the relations between parts
of scientific method. Observation - small number of data and explains what happens
Hypothesis – small number of data and explains why it happens
Law – large number of data and explains what happens
Theory – large number of data and explains why it happened
Scientific Method: Additional
Points
• Scientist are human.
• “just a theory” in every day conversation.
• Theories are not equal to truth.
• Theories are the closest to truth one can get
using the scientific method.
• General steps in chemistry
Macroscopic Observations
Microscopic ExplnationsTro's "Introductory Chemistry",
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1.5 A Beginning Chemist: How
to Succeed
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How to Succeed in Chemistry
• Be curious and use your imagination.
Explore and investigate.
• Quantify and calculate
Even small differences can be important!
• Commitment
Work regularly and carefully.
Figure from page 6
of students working on
An archeology dig
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The Best Approach to
Learning Chemistry• Learn the vocabulary of chemistry.
Definitions of terms.
How common vocabulary is applied to chemistry.
• Memorize important information.
Names, formulas, and charges of polyatomic ions.
Solubility rules.
• Learn and practice processes.
Systematic names and formulas.
Dimensional analysis.
• Do the questions and exercises in the chapter to test your understanding and help you learn the patterns?
Additional Tips
• Read the text.
• Work in chapter problems as you read.
• Work end of chapter problems
• Work old quizzes
• Attend class
• Attend Lab
• Visit web site frequently
• Seek help if you need it
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