Calculating Density PPT

1. NKCSD eChemistry
Calculating Density

2. Common Chemistry Measurements
Density (D)
• Density is a measure of the
amount of mass in a given
volume (D = m/V), measured in
g/cm3 or g/mL.
• It is determined by first finding
the mass and the volume of the
object. Then, density is the mass
of the object divided by its
volume. 2

3. Density
All substances have density.
• Liquids – The more dissolved solids in a solution,
the denser the liquid. Cold water is more dense
than warm water and will sink.
• Solids – Ice is less dense than water and will float.
Various rocks, woods, and metals have a
characteristic density specific to that substance.
• Gases – Cold air is more dense than warm air and
will sink (the greater the kinetic energy, the
greater the volume, and the less dense the gas).
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4. Density
Which diagram represents the liquid layers in the
cylinder? K – Karo syrup (1.4 g/mL)
V – vegetable oil (0.91 g/mL)
W – water (1.0 g/mL)
V
V
V
KK
K
K
W
W
W
a) b) c) 4

5. Calculating Density
When solving density problems, we will use the
GUESS method!
G U E S S
GIVEN
“What’s given
in the
problem”
UNKNOWN
“What we are
looking for”
EQUATION
“Write the
equation”
SUBSTITUTION
“plug numbers
into the
equation”
SOLUTION
“answer with
correct
label/units
and round to
the nearest
0.001”
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6. Calculating Density
Gasoline has a mass of 23.54 g and a volume
of 124.3 mL. What is the gasoline’s density?
Givens Unknown Equation Substitution Solution
m = 23.54 g
v = 124.3 mL D D = m/v 23.54
124.3
0.189 g/mL
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7. Calculating Density
The density of aluminum is 2.7 g/mL. What is
the volume of 12.4 g?
Givens Unknown Equation Substitution Solution
D = 2.7 g/mL
m = 12.4 g
v v = m/D 12.4
2.7
4.593 mL
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8. Calculating Density
The accepted density for copper is 8.96 g/mL.
Calculate the mass of a 25.0 mL sample of
copper.
Givens Unknown Equation Substitution Solution
D = 8.96 g/mL
v = 25.0 mL
m m = Dv 8.96 (25.0) 224 g
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