Download Atoms have a structure that determines their properties.

6.1
Properties Are Used to Identify Matter
• Physical properties can be observed without changing
the chemical structure of a substance.
• Chemical properties describe a possible chemical
change.
• Matter is made of atoms.
• Atoms are the smallest particles of each element.
• Elements, compounds, and mixtures together
constitute all matter.
• Mixtures are made from two or more substances
that are not chemically combined.
• Elements combine to form compounds.
• Elements are identified by names and chemical symbols.
• Some elements are found as paired atoms.
VOCABULARY
physical properties
chemical properties
mixtures
pure substances
elements
atoms
compounds
6.2
Atomic Theory
• Atoms are made of component particles
called subatomic particles: protons,
neutrons, and electrons.
• Every atom of any one element will
have the same number of protons.
VOCABULARY
subatomic particles
nucleus
protons
neutrons
atomic number
• Positive protons and neutral neutrons
are found in the nucleus, and negative
electrons are arranged in shells or
orbits around the nucleus.
• There are an equal number of protons
and electrons in an atom. Ions form
when the number of electrons changes.
• The number of electrons in the outer
shell determines the properties of the
element.
mass number
atomic mass
electrons
electron shells
unpaired electrons
paired electrons
6.3
Classifying Elements with the
Periodic Table
• Elements can be classified or grouped in many
different ways using physical and chemical properties.
VOCABULARY
chemical families
• The groups include metals, non-metals, and metalloids.
• Some groups of elements have characteristic sets of common
physical and chemical properties, and are called chemical families.
• The Periodic Table organizes elements in the following way:
• Metals are found on the left side,
non-metals on the right, and metalloids
in between.
• Chemical families are arranged in
vertical groups.
• The table can also display the chemical
symbol, atomic number, atomic mass, ion
charge, density, and other information
about each element.
CHAPTER
6
Elements, Atoms, and the Atomic Theory
• Matter is made of atoms and every element has its own unique
type of atom.
• Elements are identified by names and chemical symbols.
• Atoms have a structure that determines their properties.
• Every atom is composed of three types of subatomic particles:
protons, neutrons, and electrons.
• The number of electrons in the outer shell of an element’s atoms
determines the properties of the element.
CHAPTER
6
Elements, Atoms, and the Atomic Theory
• The Periodic Table organizes elements in different ways.
• Metals are found on the left,
non-metals on the right,
and metalloids in between.
• Chemical families are arranged
in vertical groups.
• Periodic Tables can indicate the chemical symbol, atomic number, atomic
mass, ion charge, density, and other information about each element.
CHAPTER
6
Elements, Atoms, and the Atomic Theory
Activity
Draw your own Classification of Matter chart in your notebook. Use the
example below as a guide. Under each heading, write at least three
common examples of each form of matter.
See pages 149–150 in the textbook for clarification and a description of
each heading if needed.
CHAPTER
6
Elements, Atoms, and the Atomic Theory
Key Ideas
• Matter is made of atoms.
• Atoms have a structure that determines their properties.
• The Periodic Table organizes elements in different ways.