Chemistry: The Study of Matter

1
Chemistry The Study of Matter

• Matter and Change

2
What is Chemistry
3
What is Chemistry?

• The study of the composition, structure, and
  properties of matter, the processes that matter
  undergoes, and the energy changes that accompany
  these processes.

4
Chemistry is

• A natural science.
• a language with its own vocabulary.
• a way of thinking.
• Chemicals are any substance that has a definite
  composition.

5
Branches of Chemistry

• Applied Chemistry is the use of chemistry to
  attain certain goals, in fields like medicine,
  agriculture, and manufacturing.
• Pure chemistry gathers knowledge for knowledge
  sake.
• Theoretical chemistry is the use of mathematics
  and computers to understand the principles behind
  observed chemical behavior and to design and
  predict the properties of new compounds

6
Branches of Chemistry

• Analytical Chemistry studies composition of
  substances.
• Inorganic Chemistry is the study of substances
  without carbon
• Organic Chemistry is the study of compounds
  containing carbon
• Biochemistry is the study of the chemistry of
  living things
• Physical Chemistry studies behavior of substances

7
Branches of Chemistry

• Basic Research is carried out for the sake of
  increasing knowledge.
• how and why a specific reaction occurs
• what the properties of a substance are
• the discovery of Teflon
• Applied Research is generally carried out to
  solve a problem.
• development of new refrigerants

8
Branches of Chemistry

• Technological Development typically involves the
  production and use of products that improve our
  quality of life.
• computers
• catalytic converters in cars
• biodegradable materials
• Basic research, applied research, and
  technological development often overlap

9
Top 8 Chemicals made in the US
10
CNBW Chemistry Notebook Work

• In your chemistry notebook there should be a
  section for practice problems and review problems
  that will be apart of the lecture. When you see
  a slide marked CNBW go to that page and do the
  problems in your notebook.
• Page 5
• 1- 3

11
Matter and Its Properties
12
What is Matter?

• Volume is the amount of three dimensional space
  that an object occupies.
• Matter is anything that takes up space and has
  mass.
• Mass is the amount of matter in an object.
  Measure mass using a balance.
• Mass is resistance to change in motion along a
  smooth and level surface.
• Weight is he amount of gravity pulling on an
  object. Measured using a scale.

13
Building Blocks of Matter

• Atom the smallest unit of an element that
  maintains the chemical identity of that element.
• Elements - simplest kind of matter.
• Pure substance.
• Cannot be broken down into a simpler or more
  stable form.
• All one kind of atom.

14
Building Blocks of Matter

• Compounds are substances that can be broken down
  by chemical methods into simpler substances.
• Each compound is made from the atoms of two or
  more elements.
• When they are broken down, the pieces have
  completely different properties than the
  compound.
• Molecules smallest unit of a substance made of
  one or more kinds of atoms.

15
Molecule
16
Molecules
17
Properties of Matter

• Extensive properties depend on the amount of
  matter that is present.
• volume
• mass
• the amount of energy in a substance.

18
Properties of Matter

• Intensive properties do not depend on the amount
  of matter present.
• melting point
• boiling point
• density
• ability to conduct electricity
• ability to transfer energy as heat

19
Properties of Matter
20
Physical Properties

• Words that describe matter (adjectives)
• Physical Properties- a property that can be
  observed and measured without changing the
  substance.
• Examples?
• Melting point
• Boiling point

21
Physical Changes

• Physical change - A change in a substance that
  does not involve a change in the identity of the
  substance.
• Examples?
• Cutting
• Grinding
• Boiling
• Melting

22
States of matter

• Solid- matter that can not flow and has definite
  volume.
• Liquid- definite volume but takes the shape of
  its container (flows).
• Gas- a substance without definite volume or shape
  and can flow.
• Vapor- a substance that is currently a gas but
  normally is a liquid or solid at room
  temperature.
• Plasma a high-temperature physical state of
  matter in which atoms lose most of their electrons

23
Plasma
24
Water in Three States
25
States of Matter
Definite Volume?
Definite Shape?
Temp. increase
Com-pressible?
Small Expans.
Solid
YES
YES
NO
Small Expans.
Liquid
NO
NO
YES
Large Expans.
Gas
NO
NO
YES
26
Liquid
Gas
Solid
27
Chemical Properties

• Chemical Properties- relates to a substances
  ability to undergo changes that transform it into
  different substances.
• Chemical changes - a change where one or more
  substances are converted into different
  substance. (AKA chemical reaction)
• Examples?
• Burning
• Cooking

28
Chemical Reactions

• Reactants The substances that react in a
  chemical change (stuff you start with)
• Products The substances that are formed by the
  chemical change (what you make).
• NEW PROPERTIES
• Not easily reversed

reactants
product carbon oxygen ? carbon dioxide
29
Indications of a chemical reaction

• Energy absorbed or released
• Color change
• Odor change
• Precipitate- solid that separates from solution
• Not easily reversed

30
Indications of a chemical reaction
31
Electrolysis of Water
32
Comparison of Physical and Chemical Properties
33
Energy and Changes in Matter

• Energy is always involved when physical or
  chemical changes occur.
• Energy can be in various forms.
• heat
• light
• Law of Conservation of Energy.
• Energy can be absorbed or released in a change,
  it is not destroyed or created.

34
Classification of Matter
35
Classifying Matter
36
Mixtures

• Made up of two substances, each of which retains
  its own identity and properties.
• Heterogeneous- mixture is not uniform throughout
  (not the same from place to place).
• Chocolate chip cookie
• Gravel
• soil
• Homogeneous- Uniform throughout (same composition
  throughout).
• Kool-aid, air.
• Every part keeps its properties.
• Story of Romiso

37
Types of Mixtures
38
Examples of Mixtures
39
Compound or Mixture
Compound
Mixture
40
Which is it?
41
Pure Substances

• Pure substance has a fixed composition and
  differs from a mixture in the following ways
• Every sample of a pure substance has exactly the
  same characteristic properties.
• Every sample of a pure substance has the exact
  same composition.
• Water is always 11.2 hydrogen and 88.8 oxygen
  by mass.

42
Laboratory Chemicals and Purity
43
CNBW

• Page 14
• 1 - 4

44
Elements
45
Chemical symbols

• Periodic Table more than a list of elements.
• There are 110 elements
• Each has a 1 or two letter symbol
• First letter always capitalized second never
• Some from Latin of other languages

46
Examples of Elements
47
Periodic Table
48
Periodic Table Intro

• Groups or families are the vertical columns of
  the periodic table.
• Each group contains elements with similar
  chemical properties.
• Periods the horizontal rows of elements on the
  periodic table.
• Physical and chemical properties change somewhat
  regularly across a period.

49
Types of Elements

• Metals a element that is a good electrical and
  heat conductor
• Most are solid at room temperature.
• Malleability ability to be hammered into
  sheets.
• Ductile ability to be drawn into wires.
• Tensile strength the ability to resist breaking
  when pulled.
• Conduct Moves heat and electricity well.

50
Metals Gold, Copper, and Aluminum
51
Types of Elements

• Nonmetals poor conductors of heat and
  electricity.
• Typically gases at room temperature
• Solid forms are brittle

Various nonmetal elements (a) carbon, (b)
sulfur, (c) phosphorus, and (d) iodine
52
Types of Elements

• Metalloids an element that has some
  characteristics of metals and some
  characteristics of nonmetals.
• Tend to be semiconductors.
• All are solids at room temperature.
• Noble gases unreactive elements in the last
  group.
• Gases at room temperature (as the name implies)

53
CNBW

• Page 20
• 1 - 5