DENSITY and TEMPERATURE
It’s time to get at that work
Density
• DENSITY = MASS / Volume
• d=m/v
• Density is an INTENSIVE property. Why?
Density
• High density –Molecules are closer together
• Low Density – Molecules are further apart
Density - SOLVE
• Gold (Au) is a substance that is chemically
unreactive. A piece of gold ingot (molded
material) has a mass of 301g and a volume of
15.6cm3. Calculate the density.
• d=m/v
Set up the equation
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d=m/v
d = 301g / 15.6cm3
d = 19.29487179 g/cm3
d = 19.3 g/cm3
Density Solve again!!
• Mercury (Hg) is the only metal that is liquid at
room temperature. It has a density of 13.6
g/mL. Calculate the mass of 5.50 mL of the
liquid.
Density
• d=m/v
• 13.6 g/mL = 5.50 g / v
What is the rule if our variable is in the
denominator?
Density
• CROSS MULTIPLY THE VARIABLE FIRST!!!!
• (v) 13.6 g/mL = 5.50 g (v)
v
(v) 13.6 g/mL = 5.50 g
13.6 g/mL 13.6 g/mL
V = 0.404411765 g
V = 0.404 g
Temperature
• Temperature is also an intensive property
• IT is NOT a measurement of ‘hot’ or ‘cold’
• Temperature is a measurement of kinetic
energy (mass in motion)
• When there is less kinetic energy, substances
freeze
• When there is more kinetic energy, substances
heat up
Temperature
Fahrenheit (F°)
Celsius (C°)
Kelvin (k)
Kelvin is an absolute number
K = C° + 273.15
C° = (F° - 32°) X 5/9
F° = 9/5 X (C° + 32°)
c °= k – 273.15
THE DENSITY LAB DAY 1
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1) Measure the Beaker
2) Measure the volume of water
3) POUR water into beaker
4) Measure water + beaker
5) EXPERIEMENT WITH EGG
6) Add salt
7) Measure SALTwater + beaker, and VOLUME
8) EXPERIMENT WITH EGG AGAIN!!!!!
The density of Aluminum is 2.7 g/mL.
The volume of a particular sample is
3.0 mL. Calculate to find the mass.
• d=m/v
• 2.7 g/mL = m / 3.0 mL
• m = 8.1 g
An object has a mass of 7.5 g and a
volume of 5.0 mL. Solve to find the
density of this object.
• d=m/v
• d = 7.5g / 5.0 mL
• d = 1.5 g/mL
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435°F = _____C°
C° = (F° - 32°) X 5/9
C° = (435° - 32°) X 5/9
C° = (403°) X 5/9
C° = 2015 /9
C° = 224°
K = C° + 273.15
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31°C = ______k
K = C° + 273.15
K = 31° + 273.15
K = 304.15k
F° = 9/5 X (C°) + 32°
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-269°C=_____F°
F° = 9/5 X (C°) + 32°
F° = 9/5 X (-268°) + 32°
F° = 9/5 X -236°
F° = -425.8°
K = C° + 273.15
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234.3k = _____C°
K = C° + 273.15
234.3 = C° + 273.15
234.3 – 273.15 = C° + 273.15 – 273.15
C° = -38.85°
Does the addition of SALT to the
water make a difference? Why or
Why not?
• Why do you think the egg sank or floated in
the salt water in comparison to the regular
water?
• What property of the egg caused the egg to
sink or float? Is this property extensive or
intensive? Why or Why not?
DENSITY LAB DAY 2
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Measure the volume of the wooden block
Measure the mass of the wooden block
Measure the beaker
Measure the volume of the water
Measure the mass of the water
EXPERIMENT with the block