Matter

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Unit 1
Introduction to
Chemistry and
Matter
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Chapter 1
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Physical Science review
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Section 1.1 Objectives
 Define Chemistry
 List examples of the branches
of chemistry
 Compare and contrast basic
research, applied research, and
technological development.
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What is Chemistry?
 Chemistry is the study of the
composition, structure, and
properties of matter and the
changes it undergoes
 It deals with questions such as,
What is material made of? What
is its make up? How does it
behave when heated or cooled?
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Branches of Chemistry
 Organic Chemistry - the study of
carbon containing compounds.
 Inorganic Chemistry - study of all
substances that do not contain
carbon.
 Physical Chemistry - study of the
properties, changes, and
relationships between energy and
matter.
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Branches Continued
 Analytical Chemistry - identification
of the components and composition
of materials.
 Biochemistry - study of substances
and processes occurring in living
things.
 Theoretical Chemistry - the use of
mathematics and computers to
design, predict, and understand the
properties of new compounds.
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 In all areas of chemistry,
scientists work with chemicals.
 A chemical is any substance that
has a definite composition.
 Example: Sucrose is a sugar. It has
definite composition in terms of
atoms that compose it (C, H, and O
Atoms).
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Basic research
 Basic Research
 Goal: To increase knowledge,
such as, how and why a specific
reaction occurs or what the
properties of a substance are?
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Applied Research
 When using applied science,
scientists are not driven by pure
curiosity, but by a need to solve
a problem created by specific
needs.
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Technological
development
 Technology employs existing
knowledge gained from basic
and applied research to make
life easier or more convenient.
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Section 1.2 Objectives
 Physical Properties vs. Chemical
Properties
 Classify changes in matter as
physical or chemical.
 Explain the gas, liquid, and solid
states in terms of particles.
 Explain how the law of conservation
oe energy applies to changes in
matter.
 Mixture vs. a Pure Substance.
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1.2 Matter and Its
Properties
 Mass is the measure of the amount of
Matter
 Volume is the amount of space something
takes up
 Matter is anything that has mass and
takes up space
 The fundamental building block of
matter are atoms
 These particles make up elements and
compounds.
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Atoms, Elements, and
Compounds
 An atom is the smallest unit of an
element that maintains the
properties of that element.
 An element is a pure substance made
of one kind of atom.
 A compound is a substance that is
made from the atoms of two or more
elements that are chemically
bonded.
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Properties and Changes
in Matter
 Chemists use properties
(characteristics) to distinguish
between substances and to
separate them.
 Extensive properties depend on
the amount of matter present
 Example - mass, volume, energy in a
substance
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Properties cont Intensive properties do not
depend on the amount of matter
Present.
 Example - melting point, boiling
point and density
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Physical Properties and
Physical Changes
 A physical property is a
characteristic that can be observed
or measured without changing the
identity of the substance.
 Examples : melting and boiling point
 Physical change - a change in a
substance that does not involve a
change in the identity of a substance.
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Chemical Properties and
chemical Changes
 A chemical property relates to a
substances ability to undergo
changes that transform into
different substances.
 A change in which one or more
substances are converted into
different substances is called a
chemical change or chemical
reaction.
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Chemical Changes
 Substances that react are called
reactants.
 Substances that are formed are called
products.
 1CH4 (g) + 2O2 (g)
1CO2 (g) + 2H2O
Reactants
Products
 Arrows and + signs can be substituted for
the words yields and plus.
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Remember: Chemical properties involve the change in the
chemical make up of a substance.
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In other words the substance
was involved in a chemical
Solids, Liquids, and Gases
 Change of State - a physical change
of a substance form one state to the
other
 Matter in the solid state has definite
volume and definite shape. Particles
are closely packed.
 Matter in the liquid state has
definite volume but not definite
shape. Particles are loosely packed
 Matter in the gas state has neither
definite volume or shape. Particles
are free to roam container.
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Tightly packed
Loosely packed
Free to roam
(fixed positions) (can slide past one another)
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Classification of
Matter
 All matter can be classified into one
of two groups: Pure Substances or
Mixtures.
 Pure Substances, which can be
elements or compounds.
Compounds are atoms of more than
one element coming together to
form a new substance.
 The composition of a pure substance is
the same through out and does not vary
form sample to sample.
 Example : The element Carbon or the
compound COMatter
- carbon
monoxide
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Pure Substances vs..
Mixtures cont In contrast, Mixtures contain more
than one substance.
 They can vary in composition and
properties from one part of a sample to
another part of the same sample
 Mixtures are therefore a blend between
two or more pure substances
(compounds or elements) each of which
retains its own properties.
 Example: KoolAid - Sugar + water
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Mixtures
 Mixtures can be one of two
types:
 Homogenous
 Heterogeneous
Homogeneous are uniform in
composition. They are referred to
as solutions.
Heterogeneous mixtures are not the
same throughout.
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Section 1.3 Objectives
 Describe the arrangement of
the periodic table.
 List the characteristics that
distinguish metals, nonmetals,
and metalloids.
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Section 1-3 Elements
And review of the
Periodic Table
 Elements are pure substances
that cannot be broken down by
chemical changes.
 The elements are organized into
groups called the periodic
table.
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The Periodic Table
 The vertical columns of the periodic
table are called groups.
 The horizontal rows of elements are
called periods.
 The two sets of elements placed
below the table make up the
lanthanide and actinide series.
 These metallic elements fit into the
table just after elements 57 and 89.
 They are placed below so the table
isn’t too wide and can be fit on one
sheet of paper.
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Types of Elements
 The P.T. is divided into two main
sections: Metals and Nonmetals
 Metals are located to the left and in
the middle.
 Nonmetals are located on the right
 The stair step line shows
characteristics of both metals and
nonmetals. These are called
metalliods
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Metals
 A metal is an element that is a good
conductor of heat and electricity.
 Not extraordinarily hard
 Properties: Malleability (can be
hammered into thin sheets), ductile
(can be drawn into fine wire), and
have high tensile strength (the
ability to resist breaking)
 Luster – the shininess of a metal
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NonMetals
 A nonmetal is an element that is
a poor conductor of heat and
electricity.
 Usually found in gaseous form
@ room temperature.
 Bromine is a liquid @ room temp.
 If in solid form are Brittle
 Example - Sulfur
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Metalliods
 A metalliod is an element that
has some characteristics of
metals and some
characteristics of nonmetals
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