What is matter?
An object that takes up space and
has mass.
What is pure substances?
Has the same composition
(is homogeneous)
and the same properties throughout
the sample.
Amount does not matter.
What is an element?
• An element is a pure substance
and cannot be broken down any
further.
What is a compound?
Two or more elements
chemically combined.
What is a mixture?
Two or more substances
physically combined and they
can easily be separated.
What is a solution?
Two or more substances that are
dissolved together and you cannot
tell apart the particles.
What is a solute?
The substance that is being dissolved.
What is a solvent?
The substance that does the dissolving.
What does heterogeneous mean?
It means two or more different
substances that are easily identifiable.
Think: peas & carrots
trail mix
What does homogeneous mean?
Two or more substances combined
and it is even throughout.
Think: Hawaiian Punch
black coffee
What is a physical property?
Characteristics you can observe
using your senses.
(blue, round, hard etc.)
What is a chemical property?
Non observable characteristics,
how a substance reacts with other
elements
What is a physical change?
Changes in the appearance but
doesn’t change its makeup/identity.
What is a chemical change?
Nonreversible and something new
is created. In other words, the
original substance is changed.
What are the five signs of a chemical
change?
1) Change of color or odor
2) Gas is formed
3) Energy is given off (sound or light)
4) Change of temperature
5) Formation of a precipitate
What kind of characteristics
properties are melting point,
boiling point and density?
Melting, boiling point and
density are all physical
characteristics/properties
How do you increase the rate of
reaction?
Add heat/energy - heat makes
molecules move faster causing a
faster chemical reaction
The reverse is true; remove heat and
you will get a slower/lower rate of
reaction.
What is an atom?
• An atom makes up an element and
is the smallest unit of matter.
What is the nucleus of an atom?
• The nucleus is the center of the
atom where the protons (+) and
neutrons are found.
What subatomic particles make up
an atom?
protons, neutrons, electrons
Which subatomic particle is
positively charged?
Which subatomic particle
is negatively charged?
Which subatomic particle
has no charge?
Positive – Proton
Negative – Electron
No Charge - Neutron
What is a group/family on the
periodic table of elements?
• A group/family share similar
characteristics, and they are the 18
columns on the periodic table.
What is a period on the periodic
table of elements?
A period is the seven rows across
the periodic table.
On the periodic table of
elemets – which has similar
characteristics – a
group/family or a period?
Group/family – going down the
columns has the same
characteristics.
What is the atomic number?
The number protons/electrons in an
atom.
(How the atom is listed on the
Periodic Table of Elements
# of protons = #electrons
What is the atomic mass?
The sum of the protons and
neutrons in an atom.
What is a chemical symbol?
A chemical symbol is a notation
of one or two letters representing
a chemical element.
Also known as an element symbol.
Ex:
H is the chemical symbol for hydrogen
C is the chemical symbol for carbon
Si is the chemical symbol for silicon
How is an atom identified on the
Periodic Table?
Atoms are identified on the
periodic table by their atomic
numbers.