Download Section Notes Ch 2

CHAPTER 2
SECTION 1
1. Matter is described by its properties and may
undergo changes.
2. Everything in the universe that you can see is made
up of matter.
Matter and Volume
1. All matter takes up space, therefore all matter has
volume.
2. Objects with volume cannot occupy the same space
at the same time.
3. The volume of a liquid can be measured using a
graduated cylinder.
4. To determine the volume of a liquid, take a reading
at the bottom of the meniscus. The reading will
usually be in milliliters.
5. The meniscus is the curve at the surface of the
liquid.
6. The volume of a solid object is determined by
measuring the length, width, and height of the
object and then calculating.
7. The formula to determine the volume of a square or
rectangle is
V=lx wx h
8. The formula to determine the volume of a cylinder
is
V = Π r2h
9. The basic units on volume are cubic meters. The
basic unit may have a prefix in front of it.
10. To determine the volume of an irregularly shaped
object, use the water displacement method.
11. Place the object in a graduated cylinder with a premeasured amount of water. Take a reading at the
bottom of the meniscus. The units will usually be
in milliliters.
12. The amount of water displaced by the object is
equal to its volume.
13. The volume of liquids can be expressed in liters or
cubic units because of the following mathematical
relationship:
1 ml = 1 cm3
Matter and Mass
1. All matter has mass.
2. The mass of an object is the same, no matter where
in the universe it is located.
3. An object’s mass only changes if the amount of
matter making it up changes.
4. Weight is a measure of the force with which gravity
pulls on an object’s mass.
5. Since weight is a force, the unit on weight is a
newton (N).
6. All objects with mass exert a gravitational pull.
7. The strength of the gravitational pull on an object is
determined by 2 factors:
a. by the mass of the objects involved
b. by the distance between the objects involved
8. The greater an object’s mass, the stronger the pull
of gravity will be on the object and the greater the
object’s weight will be.
9. For every 1 kg of mass an object has,
gravity pulls on that object with a
force of 9.8 N.
10. An object’s weight changes depending on where it
is in the universe because gravity’s pull is not the
same everywhere in the universe.
11. More massive planets such as Jupiter have
stronger gravitational pulls, so your
weight would be greater if you could
stand on that planet.
Inertia
1. Inertia is defined as the tendency of an object to
resist a change in its motion.
2. Mass is a measure of inertia because the greater an
object’s mass, the greater its inertia.
3. The greater an object’s mass the harder it is to stop
or start moving.
SECTION 2
1. Knowing the properties of an unknown object
can help you determine the identity of the
object.
Physical Properties
1. A physical property is defined as a characteristic
that can be observed or measured without changing
the matter’s identity.
2. Examples of physical properties:
color
odor
magnetism
shape
strength
density
boiling/melting point
mass
volume
size
conductivity
solubility freezing point
3. Density is one of the easiest-to-identify properties.
4. The greater the density the greater the likelihood the
matter will sink. The lower the density the greater
the likelihood the matter will float.
5. The density of water is 1 g/ml (or 1 g/cm3). That is
the standard to which all other densities are
compared.
Physical Changes Do Not Form New Substances
1. A physical change is defined as a change that
affects only the physical properties of a substance.
No change in identity occurs.
2. Examples of physical changes:
change in size
change in state
change in shape
dissolving
SECTION 3
1. Besides physical properties, matter also has
chemical properties.
Chemical Properties
1. Chemical properties are defined as characteristics of
matter that are based on its ability to change into
new matter that has different properties.
2. Examples of chemical properties:
 flammability – ability to burn
 reactivity – ability to combine with other
substances
3. Chemical properties are not as easily observed as
physical properties.
Chemical Changes and New Substances
1. A chemical change is where one or more substances
are changed into new substances that have
properties that are different than the original
substances.
2. Chemical properties describe which chemical
changes will and will not occur.
3. Chemical changes are the processes by which
substances actually become new substances.
4. Examples of chemical changes:
rust
burning
spoilage
baking
formation of a gas from a solid and a liquid
formation of a solid from two liquids (precipitate)
5. Signs of a chemical change:
color change
odor change
fizzing
production of heat
foaming
emission of sound/light
6. Chemical changes change the identity of matter.
Some chemical changes can be reversed by
additional chemical changes.
7. Physical changes can usually be easily reversed.