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Objectives
 PSc.2.1.3
– Compare physical and chemical
properties of various types of
matter.
Physical Properties
 Physical
properties are
characteristics that a sample of matter
exhibits without any change in its
identity.
 This property can be observed and
measured without changing the
identity of the substance.
Physical Properties
 Examples
of the physical properties
of a chunk of matter include its:
 solubility
 boiling
 melting
 density
point
 color
 electrical
 and
point
 magnetic
conductivity
physical state (solid, liquid or gas)
Physical Properties
 Salt
is
soluble in
water.
 Water
boils at
100°C.
Chemical Properties
 Chemical
Properties are properties of
matter that describes a substance’s
ability to participate in chemical
reactions.
 A chemical property describes how a
substance changes into a new
substance, either by combining with
other elements or breaking apart into
new substances.
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Chemical Properties
 Examples:
– Reactivity- the ability of a substance to
combine chemically with another
substance.
– Flammability- the ability of a substance to
react in the presence of oxygen and burn
when exposed to a flame.
– In general, the ability of a substance to
react…to form…
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Chemical Properties
 You
can observe chemical properties
only in situations in which the identity of
the substance changes.
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Physical vs. Chemical Prop.
 Classify
the following properties as
either chemical or physical.
red color
density
flammability
solubility
reacts with acid to
form hydrogen
supports
combustion
bitter taste
melting point
reacts with water
to form a gas
reacts with a base
to form water
hardness
boiling point
can neutralize a
base
luster
odor
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Physical vs. Chemical Prop.

Physical Properties
–
–
–
–
–
–
–
–
–
Red color
Density
Solubility
Bitter taste
Melting point
Hardness
Boiling point
Luster
Odor

Chemical Properties
– Reacts with acid to form
hydrogen
– Supports combustion
– Reacts with water to
form a gas
– Reacts with a base to
form water
– Can neutralize a base
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Density
 Density
is the amount of matter (mass)
contained in a unit of volume.
 Styrofoam has a low density or small
mass per unit of volume.
Density
mass
density 
volume
m
V D
Density
 Solving
Density Problems
– Cover the variable you are solving for
– If you cover the top variable, multiple
the bottom ones
m
V D
To solve for mass,
multiply volume by
density.
Density
 Solving
Density Problems
– Cover the variable you are solving for
– If you cover a bottom variable, take
the top variable and divide by the
bottom
m
V D
To solve for
volume, take mass
and divide by
density.
 Calculate
the mass for an object having a
density of 19 g/mL and a volume of 5.0 mL.
GIVEN:
WORK:
D = 19 g/mL
V= 5.0 mL
m=?
m
m= VxD
m = (19 g/mL) (5.0 mL)
m = 95 g
V D
 Calculate
the volume for an object having
a mass of 18 g and a density of 12 g/mL.
GIVEN:
WORK:
m = 18 g
D = 12 g/mL
V=?
m
V=m÷D
V = (18 g) ÷ (12 g/mL)
V = 1.5 mL
V D
Density
Solve the following density
problems.
1. The density of sugar is
1.59 g/cm3. Calculate the mass
of sugar in 15.0 mL.
(1 mL = 1 cm3)
23.9 g
Density
2. The density of helium is
0.178 g/L. Calculate the volume
of helium that has a mass of
23.5 g.
132 L
Density
3. A 14.95 g sample of gold has a
volume of 0.774 cm3.
Calculate the density of gold.
19.3 g/cm3
Density
4. Balsa wood has a density of
0.12 g/cm3. What is the mass
of a sample of balsa wood if
its volume is 134 cm3?
16 g
Density
5. The density of ice at 0 °C is
0.917 g/cm3. Calculate the
volume of 145 g of ice.
158 cm3
Quiz
1.
2.
3.
4.
The temperature at
which a solid
becomes a liquid.
Ability of a substance
to burn in the
presence of oxygen.
Ability of a substance
to combine
chemically with
another substance.
Mass per unit volume
of a substance.
a.
b.
c.
d.
e.
Melting point
Boiling point
Density
Reactivity
Flammability
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