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Density

Name: Kenneth Tan Jun WeiClass: 102Index Number: 16ACE: Term 2

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WhatWhat isis Density?Density?

• Known as mass per volumeKnown as mass per volume• Used to measure a material or objects Used to measure a material or objects

compactness compactness • A form of describing mass in a A form of describing mass in a

continuous systemcontinuous system

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Factors that affect DensityFactors that affect Density

• Mass of an objectMass of an object• Volume of an objectVolume of an object• What kind of state is the object in What kind of state is the object in

e.g. solid state, liquid state, gaseous e.g. solid state, liquid state, gaseous statestate

etcetc• Regular or irregular shapedRegular or irregular shaped

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Units of DensityUnits of Density

• SI unit for Density is kg/m or g/cmSI unit for Density is kg/m or g/cm• One thousand kilograms per cubic One thousand kilograms per cubic

meter equals one gram per cubic meter equals one gram per cubic centimeter [1000 kg/m = 1 g/cm ]centimeter [1000 kg/m = 1 g/cm ]

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3 3

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Formula to finding DensityFormula to finding Density

Formula: Formula:

Density= Density=

E.g. The mass of iron is 27kg and its E.g. The mass of iron is 27kg and its volume volume

is 3m , find the density of iron.is 3m , find the density of iron.

Density=Density=

=9kg/m=9kg/m

Mass

Volume

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27kg

3m3

3

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Steps taken to find Density of an Steps taken to find Density of an objectobject

Step 1: Measure the mass and volume Step 1: Measure the mass and volume of the of the substance substance

Step 2: Divide the mass of the Step 2: Divide the mass of the substance by substance by

its volumeits volume

Density=Density=

MassVolume

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Steps taken to find density of a Steps taken to find density of a regularly shaped objectregularly shaped object

Step 1: Measure the mass and Step 1: Measure the mass and calculatecalculate

from dimensions, the volume from dimensions, the volume of of the object the object

Step 2: Density= Step 2: Density=

Mass

Volume

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Steps taken to find density of an Steps taken to find density of an irregularly shaped objectirregularly shaped object

First place the egg on a measuring scale First place the egg on a measuring scale and you will be able to find the egg’s and you will be able to find the egg’s mass.mass.

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Next, fill the eureka beaker until water Next, fill the eureka beaker until water starts flowing out of its spout. Allow it starts flowing out of its spout. Allow it to stand until it stops to flow.to stand until it stops to flow.

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Then, place a measuring cylinder right Then, place a measuring cylinder right below the spout and slowly lower the below the spout and slowly lower the egg into the water.egg into the water.

Density=Density=

volume of the egg=volume of the water that flows out of the spout

Mass

Volume

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Steps taken to find density of a Steps taken to find density of a liquidliquid

The steps that have to be taken to find The steps that have to be taken to find density of water is similar to the steps density of water is similar to the steps taken to find a substance.taken to find a substance.

Step 1: Measure the mass and volume of Step 1: Measure the mass and volume of the liquidthe liquid

Step 2: Divide the mass and the volume Step 2: Divide the mass and the volume ofof

the liquidthe liquid

Density=Density= MassVolume

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Steps taken to find Density of Steps taken to find Density of GasGas

Step 1:Step 1:Take the molecular formula Take the molecular formula weight of weight of the gas (grams per the gas (grams per mole—from the mole—from the periodic table) periodic table)

Step 2:Divide that by the standard Step 2:Divide that by the standard molarmolar volume for a gas, volume for a gas, which is 22.4 Lwhich is 22.4 L per moleper mole

density=density= FW

22.4

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Solids and their DensitySolids and their Density

SubstanceSubstance

PlatinumPlatinum

GoldGold

LeadLead

SilverSilver

CopperCopper

IronIron

ZincZinc

AluminiumAluminium

Ice Ice

g/cmg/cm

21.521.5

19.319.3

11.311.3

10.510.5

8.58.5

7.97.9

7.17.1

2.72.7

0.920.92

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Solids and their DensitySolids and their Density

SubstanceSubstance

GlassGlass

PinewoodPinewood

corkcork

g/cmg/cm

2.52.5

0.500.50

0.240.24

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Liquids and their DensityLiquids and their Density

SubstanceSubstance

MercuryMercuryGlycerineSea WaterPure Water( at 4 degreesCelsius)Olive OilTurpentinePetrolAlcohol

g/cmg/cm

13.2613.26

1.261.26

1.031.03

1.001.00

0.920.92

0.870.87

0.800.80

0.790.79

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Gases and their DensityGases and their Density

SubstanceSubstance

AirAir

HydrogenHydrogen

Helium Helium

Nitrogen Nitrogen

OxygenOxygen

Carbon DioxideCarbon Dioxide

g/cmg/cm

0.001290.00129

0.000090.00009

0.00016630.0001663

0.0012510.001251

0.00130.0013

0.001950.00195

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Floating and SinkingFloating and Sinking

Some objects float while others sink.Some objects float while others sink.

• The deciding factor whether the object The deciding factor whether the object floats or sinks is actually density.floats or sinks is actually density.

• Objects that float on water have a lower Objects that float on water have a lower density than water, while objects that sink density than water, while objects that sink have a higher density than water.have a higher density than water.

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Picture of objects that float and sink in water. Objects that float have asmaller density than water. While, objects that sink have a higher densitythan water.

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Sources Sources

• http://www.engineeringtoolbox.com/http://www.engineeringtoolbox.com/density-specific-weight-gravity-density-specific-weight-gravity-d_290.htmld_290.html

• karentimberlake.com/ppz/karentimberlake.com/ppz/densitydensity.ppt.ppt • http://www.sparknotes.com/testprep/http://www.sparknotes.com/testprep/

books/sat2/chemistry/books/sat2/chemistry/chapter5section11.rhtmlchapter5section11.rhtml

• http://morrisonlabs.com/http://morrisonlabs.com/density_chart.htmdensity_chart.htm

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DensityDensity

Thank you for your kind attention