Density
Name: Kenneth Tan Jun Wei
Class: 102
Index Number: 16
ACE: Term 2
1
What is Density?
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Known as mass per volume
Used to measure a material or objects
compactness
A form of describing mass in a continuous
system
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Factors that affect Density
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Mass of an object
Volume of an object
What kind of state is the object in
e.g. solid state, liquid state, gaseous state
etc
Regular or irregular shaped
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Units of Density
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3
3
SI unit for Density is kg/m or g/cm
One thousand kilograms per cubic meter
equals one gram per cubic centimeter
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3
[1000 kg/m = 1 g/cm ]
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Formula to finding Density
Formula:
Mass
Density= Volume
E.g. The mass of iron is 27kg and its volume
3
is 3m , find the density of iron.
Density= 27kg
3m
3
=9kg/m
3
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Steps taken to find Density of an
object
Step 1: Measure the mass and volume of the
substance
Step 2: Divide the mass of the substance by
its volume
Density=
Mass
Volume
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Steps taken to find density of a
regularly shaped object
Step 1: Measure the mass and calculate
from dimensions, the volume of
the object
Mass
Step 2: Density= Volume
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Steps taken to find density of an
irregularly shaped object
First place the egg on a measuring scale and
you will be able to find the egg’s mass.
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Next, fill the eureka beaker until water
starts flowing out of its spout. Allow it to
stand until it stops to flow.
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Then, place a measuring cylinder right
below the spout and slowly lower the egg
into the water.
volume of the egg=volume of the water that flows out of the spout
Density=
Mass
Volume
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Steps taken to find density of a liquid
The steps that have to be taken to find
density of water is similar to the steps taken
to find a substance.
Step 1: Measure the mass and volume of
the liquid
Step 2: Divide the mass and the volume of
the liquid
Mass
Density= Volume
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Steps taken to find Density of Gas
Step 1:Take the molecular formula weight of
the gas (grams per mole—from the
periodic table)
Step 2:Divide that by the standard molar
volume for a gas, which is 22.4 L
per mole
FW
density= 22.4
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Solids and their Density
Substance
Platinum
Gold
Lead
Silver
Copper
Iron
Zinc
Aluminium
Ice
g/cm 3
21.5
19.3
11.3
10.5
8.5
7.9
7.1
2.7
0.92
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Solids and their Density
Substance
Glass
Pinewood
cork
g/cm 3
2.5
0.50
0.24
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Liquids and their Density
Substance
g/cm 3
Mercury
13.26
Glycerine
1.26
Sea Water
1.03
Pure Water( at 4 degrees 1.00
Celsius)
Olive Oil
0.92
Turpentine
0.87
Petrol
0.80
Alcohol
0.79
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Gases and their Density
Substance
Air
Hydrogen
Helium
Nitrogen
Oxygen
Carbon Dioxide
g/cm 3
0.00129
0.00009
0.0001663
0.001251
0.0013
0.00195
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Floating and Sinking
Some objects float while others sink.
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The deciding factor whether the object
floats or sinks is actually density.
Objects that float on water have a lower
density than water, while objects that sink
have a higher density than water.
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Picture of objects that float and sink in water. Objects that float have a
smaller density than water. While, objects that sink have a higher density
than water.
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Sources
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http://www.engineeringtoolbox.com/density
-specific-weight-gravity-d_290.html
karentimberlake.com/ppz/density.ppt
http://www.sparknotes.com/testprep/books/
sat2/chemistry/chapter5section11.rhtml
http://morrisonlabs.com/density_chart.htm
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Density
Thank you for your
kind attention
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