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Chemistry chapter 1 2
What does chemistry mean to me?
Plastic Synthetic fabrics and materials Antibiotics and other drugs Chemical processes inside your
body
Chemistry chapter 1 4
What is chemistry? A physical science The study of the composition, structure,
and properties of matter and the changes it undergoes.
The science that seeks to understand what matter does by studying what atoms and molecules do. What are things made of? What are their internal structures? How do they react with each other?
Chemistry chapter 1 5
What do chemists do?
Relate properties of matter to structure of matter.
Examine properties of existing materials to produce new materials.
Chemistry chapter 1 6
Branches of chemistry Organic chemistry – most carbon-
containing compounds Inorganic chemistry – compounds that
don’t contain carbon (mostly) Physical chemistry – properties and
changes in matter and energy Analytical chemistry – identification of
components and compositions of mixtures Biochemistry – chemistry of living things Theoretical chemistry – using math and
computers to understand chemical behavior and predict new compounds
Chemistry chapter 1 7
Science and technology Science
Basic research For the sake of learning
Applied research Used to solve problems
Technology Improves the quality of life Application of science for practical
purposes
Chemistry chapter 1 8
Discuss Read the “Modern Alchemy” section
on pages 8 – 9. Discuss the following questions with
someone seated near you. Are any discoveries in this feature
accidental? Were the discoverers always aware of
what they had discovered? Why don’t we use this “new alchemy”
to make gold?
Chemistry chapter 1 9
Matter
Has mass and volume. Mass – measure of the amount of
matter measured with a balance (scale)
Volume – the amount of 3D space occupied
Chemistry chapter 1 10
Parts of matter Element – a pure substance, only 1 kind
of atom Atom – the smallest unit of an element
that has the properties of that element Compound – made from the atoms of 2
or more elements that are chemically bonded
Molecule – smallest unit of an element or compound that has the properties of that element or compound Contains more than one atom
Chemistry chapter 1 12
Properties can be … Extensive – depend on the amount of
matter present Length Mass Volume Amount of energy in a substance
Intensive – do not depend on amount of matter Density Melting and boiling points Color flammability
Chemistry chapter 1 13
Physical Properties Can be observed without changing
the identity of the substance Melting and boiling points Color Density Mass Length volume
Chemistry chapter 1 14
Physical changes
Do not involve a change in the substance Grinding Cutting Melting Boiling folding
Chemistry chapter 1 15
State changes
Type of physical change Change from one state of matter
(solid, liquid, gas, or plasma) to another Melting or freezing Boiling or condensing
Chemistry chapter 1 17
Liquids
Have definite volume, but indefinite shape Take the shape of their container
Particles are able to slip past each other
Chemistry chapter 1 18
Gases
Have indefinite shape and indefinite volume Expand to fill any container
Particles can slip past each other and are usually far apart
Chemistry chapter 1 20
Chemical Properties
Related to the ability to undergo change
Can only be observed in a chemical reaction Ability to
Rust Burn Rot
Chemistry chapter 1 21
Chemical change
When one or more substances are changed into different substances
Also called chemical reaction Before the change the substances
are called reactants After the change they are called
products
Chemistry chapter 1 22
Mixtures
Contain two or more kinds of matter Not chemically combined Can be separated by physical means
Homogeneous – the same throughout Heterogeneous – not the same
throughout
Homogeneous mixtures are also called solutions
Chemistry chapter 1 23
Pure substances
Elements or compounds Chemically combined Every sample has the same
composition
Chemistry chapter 1 25
The Periodic Table
Way to organize the elements Groups of elements– vertical
columns Periods of elements – horizontal
rows
Chemistry chapter 1 26
Groups
Numbered 1 to 18 Elements have similar chemical
properties Have similar bonding abilities Also called families
Chemistry chapter 1 27
Periods
Physical and chemical properties change across a period
Elements are more similar to others that are close to them
Chemistry chapter 1 28
Lanthanides and Actinides
Below the main body of the table Fit in after elements 57 and 89 Moved so that the table isn’t so
wide What if they weren’t?
Chemistry chapter 1 29
Metals
Left and center parts of the table Mostly solids at room temperature Good conductors of heat and
electricity Good tensile strength – can be
pulled without breaking Malleable – can be pounded into
sheets Ductile – can be drawn into fine wire
Chemistry chapter 1 30
Nonmetals
On the right side of the table Often gases at room temperature Solids are brittle Poor conductors of heat and
electricity
Chemistry chapter 1 31
Metalloids
Next to the stairstep line on the table
Have some properties of metals and some of nonmetals
Usually semiconductors
Chemistry chapter 1 32
Noble gases
Group 18 Generally unreactive
Only form compounds under specific lab conditions, not in nature