Unit 1: Matter and the Nature of Science

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Unit 1 Matter and the Nature of Science

• Chapters 1-3

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Chapter 1 Science Skills

• Standard Objectives
• Understand the scientific process and the nature
  of science
• 2. Conduct scientific investigations
• 3. Understand how scientific knowledge changes
  and accumulates over time as new evidence becomes
  available and as theories are tested and revise

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What is Science?

• Science System of knowledge to explain the
  natural world.
• Technology use of knowledge to solve problems.
• Technology and science are interdependent. As
  one increases, so does the other.

Galileos telescope (right) changed how we saw
the Universe.
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Physical Science The Basic Rules of Nature

• Physical Science is broken into two main
  categories
• Physics The study of matter, energy, forces and
  motion
• Chemistry Study of composition, structure,
  properties, and reactions of matter.

Both Physics and Chemistry were used to launch
the Saturn V rocket to the Moon.
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Scientific Method
The goal of a scientific method is to solve and
explain natural events.
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Scientific Method Definitions

• Hypothesis Educated, tested guess to an
  observation.
• Theory Well-tested explanation for a set of
  observations
• Laws A factual description of an observed
  pattern in nature.
• Experimental Variables
• Manipulated Variable- The variable the
  experimenter changes
• Responding Variable- The variable that changes
  in response to the manipulated variable.
• Controlled experiment- the change of only one
  variable

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Scientific Notation

• Scientific notation makes very large or very
  small numbers easier to work with.
• Numbers greater than zero, exponent is positive
• Numbers less than zero, exponent is negative.
• Examples (in class)
• When multiplying, you multiply the numbers and
  add the exponents
• Examples (in class)

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SI Units of Measurement

• Science uses SI Units of measurement to avoid
  confusion
• Two types of SI Units
• Base standard quantities (ex. Length)
• Derived combination of base units (ex. Volume)
• SI Prefixes are used to easily express amounts

Base SI Units
Common Prefixes
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Limits of Measurement

• Measurement is limited by two main properties
• Precision how exact the measurement is
• Accuracy how close a measurement is to the
  actual value

• Bulls Eyes
• (drawn in class)

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Chapter 2 Properties of Matter

• Standard Objectives
• Know and explain that physical properties can be
  used to classify among pure substance, solutions,
  and heterogeneous mixtures.
• Distinguish among chemical and physical changes
  in matter by identifying characteristics of these
  changes.

Sodium A soft metal that is highly reactive in
water.
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Classifying Matter
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Pure Substances

• Pure substances cannot be broken down into
  simpler components and still maintain the
  properties of the original substance.
• Elements a pure substance in which all the atoms
  are alike. Example Oxygen
• Compounds a pure substance in which the atoms
  of two or more elements are combined chemically.
  Example Carbon Dioxide

Graphite (Carbon)
Halite (Salt)
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Mixtures

• Mixtures are materials made up of two or more
  substances that can easily be separated by
  physical means.
• Two Types of Mixtures
• Heterogeneous mixture in which different
  materials can be distinguished easily.
• Suspension a heterogeneous mixture that contains
  visible particles that settle within a liquid.
  Pond water is an example.
• Homogenous two or more substances blended evenly
  throughout.
• Solution Substances dissolve to form a
  homogenous mixture. An example is salt water
• Colloid Intermediate particles that are not
  dissolved but dont separate. Milk is an
  example.

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Physical Properties

• Physical Property Characteristics of a material
  than can be observed or measured
• Types of physical properties
• Viscosity (resistance to flow
• Conductivity (heat or electricity)
• Malleability (bendable)
• Hardness
• Melting and Boiling Points
• Density

Liquids with different levels of viscosity.
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Chemical Properties

• Chemical Properties any ability to produce a
  change in composition of matter
• Types of chemical properties
• Flammability
• Reactivity

Crude oil is highly flammable
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Physical and Chemical Changes

• Physical changes are changes in color, shape, or
  state of matter. The identity of the element or
  compound does not change.
• Chemical Changes are changes from one substance
  to another. The identity of the substance
  changes.
• Separation of substances can be done using
  physical or chemical changes.

Distillation is used to separate liquids with
different boiling points.
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Chapter 3 States of Matter

• The average kinetic energy of a material and the
  pressure determines the state of the material.
• Four states of matter
• Solid state definite shape, definite volume
• Liquid state indefinite shape, definite volume
• Gaseous state indefinite shape, indefinite
  volume
• Plasma state
• Only occurs at very high temperatures (sun,
  lightning, space shuttle re-entry).

Argon Ice
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Kinetic Theory

• Kinetic Theory of Matter states that all
  particles of matter are in constant motion.
• The theory explains the behavior of gases,
  liquids, and solids.
• Absolute zero Found at -273.15 Celsius (or 0
  Kelvin). It is the temperature at which
  particles no longer are in motion.

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Six Types of Phase Changes
(Graphical Organizer in Class)
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Pressure

• Pressure is the result of a force distributed
  over an area.
• In a closed container, pressure is caused by the
  collision between the particles and the
  containers walls.
• Factors that affect pressure
• Temperature Increasing temperature increases
  pressure.
• Volume Reducing the volume increases pressure.
• Number of Particles Increasing the number of
  particles increases pressure.

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Boyles Law

• If you decrease the volume of a container of gas
  and the temperature is constant, the pressure of
  the gas will increase.
• Equation
• P1 X V1 P2 X V2

A piston compresses the gas in the cylinder
chamber of an engine.
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Charless Law

• The volume of a gas increases with increasing
  temperature, as long as pressure does not change.
• Equation
• V1/T1 V2/T2

The weather balloons volume will increase as it
floats higher up.
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Combined Gas Law

• When Boyles and Charless Law are combined, the
  equation is