AW Ch 1 Introduction to Chemistry The Process of Science

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AW Ch 1 Introduction to ChemistryThe Process of
Science

• Science is
• A process to explain changes in Nature
• A tool for tackling problems facing society
• The logical basis to explain observations -
  earthly and cosmic
• A framework for gaining and organizing knowledge
• More than a set of facts, science is -

1. A procedure for processing and understanding
information 2. Use of the Scientific Method as
the basis for scientific inquiry
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The Process of Science

• The Nature of Science
• Tentative - not final or absolute. Fresh evidence
  forces revaluation of previously explained
  phenomena.
• Replicable and Universal - New evidence must be
  repeatedly demonstrated for acceptance.
• Empirical - Experimentation, quantitative
  measurement, and sense perception lead to
  empirical data as foundation blocks.
• Humanistic - Science is produced by human beings,
  people seeking to find explanations of phenomena.
• Limited - Studies only matter energy of natural
  world or universe. Science does not study or
  address faith-based concepts or beliefs.

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The Process of Science

• The Nature of Science
• Probable - Science permits uncertain principles
  and probable deductions rather than absolute
  certainties.
• Imaginative in use of hypotheses, theories, and
  models.
• Holistic (the whole thing is more than its many
  parts) - The many branches such as biology,
  physics, chemistry contribute to an overall
  concept of the universe.
• Imperative - Nature of science demands action,
  decision making.
• Conceptual - Science develops concepts and
  principles it does not solve problems.
  Science provides only the processes and data for
  problem analysis. Society must resolve issues
  based on scientific, economic, political,societal
  and moral factors.

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The Process of Science

• The Scientific Method
• A logical approach using inquiry to solve
  scientific problems.
• Step 1 -- Make observations. Use of the senses
  to gather information indirectly.
• Step 2 -- Form a hypothesis (a guess or proposed
  explanation for what has been observed.)
• Step 3 -- Conduct an experiment (a means of
  testing a hypothesis.)
• A scientific experiment is valid only when it
  can be replicated
• independently by others.
• Step 4 Evaluate results. If the experiment
  proves the hypothesis
• false, go back and produce a new one. Conduct
  another experiment.
• Step 5 Form a theory (a broad and extensively
  tested explanation of why experiments give
  certain results. A theory explains why something
  happens.)

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The Process of Science

• The Scientific Method (Continued)
• Observations supporting a theory must be
  witnessed and recorded.
• Theories can change as more information becomes
  available.
• Example The green house gas theory holds that
  global
• temperatures are rising due in part to the
  release of carbon
• dioxide gas from the burning of fossil fuels by
  industrial and
• consumer products.
• Note Most of the worlds energy requirements are
  met by burning fossil fuels.

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The Scientific Method
If experiments prove a hypothesis false, a new
hypothesis must be proposed. A theory is a
broad explanation of why experiments give certain
results.
Scientific Law
A scientific law summarizes the results of many
observations and experiments. A scientific law
describes a natural phenomenon without attempting
to explain it.
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The Process of Science

• Scientific Law or Natural Law
• Statement summarizing results of many
  observations and experiments.
• Describes a natural phenomenon without attempting
  to explain why
• it occurs.
• Often expressed in simple mathematical
  relationships.
• Example 1. Law of gravity ½ mv2
• Example 2. Gay-Lussacs law P1 /T 1 P2
  /T2
• Describes what happens when a sealed,
  gas-filled container is
• heated The volume of gas is directly
  proportional to the Kelvin
• temperature at constant volume. Heating the
  container can lead to
• an explosion. Gay-Lussacs law states what
  happens a theory
• explains why.

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The Process of Science

• Pure Science / Applied Science / Technology
• Principle of cause and effect - everything that
  happens is related in a definite way to something
  that preceded it.
• Pure science (Basic science) - the search of
  knowledge of our world just so that we can
  understand it better. No interest in whether
  discoveries help in the real world. Often leads
  to development of new products and technologies.
• Applied science (Applied science) - the practical
  search for science-based solutions to needs or
  problems in the world. Carried out to solve a
  problem, e.g., find a cost effective and
  environmentally safe alternative fuel to
  gasoline.
• Technological development the production and
  use of products that improve the quality of life,
  e.g., Teflon non-stick coating material

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The Process of Science

• Two Large Divisions of Science
• Biological sciences - concerned with living
  things, the organic world, which has carbon or
  carbon compounds as principal components.
• Physical sciences - systematic study of the
  inorganic world, usually astronomy, chemistry,
  metrology, and physics.

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Chemistry as a Science

• Chemistry is
• A part of physical science.
• The study of matter including, its properties,
  composition, structure. Chemistry also studies
  physical and chemical changes in matter and the
  energy released or absorbed during these changes.
• A chemical Any substance that has a definite
  composition.
• Sucrose (table sugar) is a chemical
• River mud is not a chemical, but is composed of
  an ever changing mixture of chemical substances.

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Chemistry as a Science
Branches of Chemistry 1. Organic chemistry -
study of substances containing carbon and
hydrogen. 2. Inorganic chemistry - study of all
substances not classified as organic, or
the chemistry of all substances not containing
carbon . 3. Physical Chemistry - the study of the
properties and transformations of matter in
terms of fundamental physical processes. Lots of
math! 4. Biochemistry - the study of all
substances and processes that occur in living
things. 5. Analytical chemistry - the
identification of materials and the qualitative
and quantitative determination of the composition
of materials.
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Chemistry as a Science
Branches of Chemistry (Continued) 6. Nuclear
chemistry - the study of the properties of matter
involving the atomic nucleus. 7. Polymer
chemistry - the understanding and making of
polymers, the raw materials for plastic
objects, among other things. 8. Bioinorganic
chemistry - the study of the role of inorganic
materials in living things. 9.
Pharmaceutical chemistry - the chemistry of
drugs, medicines, and vitamins. 10. Chemical
engineering - the design, construction, and
operation of equipment required in the
chemical manufacturing processes.
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Chemistry as a Science

• The Study of Chemistry Helps You
• Understand how things work.
• Make informed opinions on issues and how to act
  on them.
• Choose a career
• Medicine/Biotechnology? (Develop new medicines
  and gene therapies)
• Industry? (Find a cost-effective replacement for
  oil-based fuels.
• (Develop lighter, stronger
  materials. Past Bronze, Iron, Steel
• Ages. Today The Age of
  Plastics)
• Healthcare professions? (Medicine, nursing,
  dentistry, pharmacy, etc.)
• Government? (Food/crop inspection, weather
  forecasting, forest service)
• Environmental protection? (Acid rain, global
  warming, pollution control)
• Agriculture? (Control photosynthesis,
  plant/animal hormone studies)

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How to Study Chemistry

• Reading the Text
• Read the assigned material before class.
• Select a quiet setting.
• Have pencil and paper at hand to jot down notes
  and questions.
• Use the Objectives at the beginning of each
  section as a list of what you need to know from
  the section.
• Read intensely in two-minute bursts. Close your
  eyes and envision what you have just read, or jot
  down the key facts.

• Taking Notes in Class
• Use blank 3-hole paper maintained in your
  notebook. (Loose sheets can get lost!)
• Recopying notes is a waste of time. Do it right
  the first time!

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How to Study Chemistry

• Reviewing Class Notes
• Review your notes as soon as possible after
  class.
• Do not wait until the test to review.
• Be selective about what you memorize. To
  memorize and to
• understand are not the same thing.

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How to Study Chemistry

• Working Problems
• Always review the sample problems in the
  assignment.
• Use this strategy
• - Plan
• - Compute
• - Evaluate (Does the answer make sense? Is it
  realistic?)
• Never spend more than 15 minutes trying to solve
  a problem. Instead
• make a note to ask the teacher or another
  student.
• Work on extra problems. The more problems you
  attempt, the more
• proficient you will become in solving them.
  Poor problem solving ability
• is a major reason that many people struggle
  in Chemistry.

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How to Study Chemistry

• Completing Homework
• Have a study buddy or someone else to listen as
  you recite what you
• have learned through two-minute bursts of
  silent reading.
• Exchange roles with your study buddy and have
  them recite to you.
• Correct each others mistakes (in a friendly
  manner, of course!)
• Make notes of chapter sections that remain
  unclear. Ask for clarification
• by the teacher during the next class period.

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How to Study Chemistry

• Preparing for Exams
• Dont panic and dont cram. It takes longer to
  learn under pressure.
• Read your notes out loud. (Helps the learning
  process.)
• Recite key ideas out loud. (Ability to do so
  proves that you understand
• the concept.)
• Study with a friend. (Good opportunity for
  recitation.)

• Taking Exams
• Get plenty of rest before the exam.
• Start with the questions that you know.

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Chemistry Study Aids

• Concept Maps
• (Example AW, p 24, or Holt, p 15) .

Power Notes
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Chemistry Study Aids
Two-Column Notes 1. Identify the main idea. 2.
Divide a blank sheet of paper into two columns
and write the main idea in the left-hand column.
3. Write the details in the right-hand column.
Summary Elements with similar properties are
placed in groups on the periodic table. All
groups are numbered. Some groups are also given
special names. Similar properties can include
degree of chemical reactivity, electron
configuration, physical characteristics, and
classification as metals (conduct electricity) or
nonmetals (non-conductors).
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Chemistry Study Aids

• K/W/L Strategy (What I know what I want to know
  what I learned)
• Read the section objectives
• Divide a sheet of paper into three columns.
• Brainstorm about what you know already and write
  your ideas in the
• first column.
• Think about what you want to know about the
  objectives and write
• these in the second column.
• While reading the section or afterwards use the
  third column to write
• down the information you learned.

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Chemistry Study Aids
K/W/L Strategy (What I know what I want to know
what I learned)
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Student Study Guide
Key Terms Analytical chemistry hypothesis physica
l chemistry Biochemistry inorganic
chemistry scientific law Chemistry observation s
cientific method Experiment organic
chemistry theory

• Concept Summary
• 1.1 Chemistry
• Chemistry is the study of the composition of
  matter and the changes that mater undergoes.
• Analytical chemistry biochemistry, inorganic
  chemistry, organic chemistry, and physical
  chemistry are the traditional divisions of
  chemistry.
• Chemistry helps you to understand your world and
  to make informed decisions about scientific
  issues. Chemistry is an excellent career for some
  people.
• Applied chemistry, or chemical technology, is
  chemistry used to attain a specific goal. Pure
  chemistry accumulates knowledge for its own sake.

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Student Study Guide

• Concept Summary
• 1.2 Chemistry Far and Wide
• Chemistry reaches into such diverse areas as
  materials science, energy, medicine, and
  biotechnology, agriculture, environmental
  studies, and astronomy and space exploration.
• Progress has its price. Every new development has
  its risks and benefits. Society must decide in
  which direction the balance shifts.
• 1.3 Thinking Like a Scientist
• The scientific method provides a logical approach
  to the solution of scientific problems.
• The steps of the scientific method include
  observations, hypotheses, experiments, theories,
  and scientific laws.
• An observation is information gathered directly
  by using the senses. An hypothesis is a proposed
  explanation or reason for what is observed. An
  experiment is a means to test an hypothesis. A
  scientific experiment must by repeatable.
• A theory is a broad and extensively tested
  explanation of why experiments give certain
  results. A scientific law describes a natural
  phenomenon but does not explain it.

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Student Study Guide

• Concept Summary
• 1.4 How to Study Chemistry
• You can study chemistry alone or in groups.
• It is important to learn the language and
  vocabulary of chemistry.
• Your textbook and notes are important aids in
  your studies.