properties of materials. free write differentiate between chemical and physical properties...
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Properties of Properties of MaterialsMaterials
Free WriteFree Write
differentiate between chemical and differentiate between chemical and physical propertiesphysical properties
list examples of eachlist examples of each
Chemical PropertiesChemical Properties
how a material interacts with another how a material interacts with another materialmaterial
““social” behaviorsocial” behavior
response to other matter (or lack of response to other matter (or lack of response)response)
reactionsreactions
Chemical PropertiesChemical Properties
Examples:Examples: burningburning reaction with acidreaction with acid reaction with waterreaction with water corrosion/rusting/oxidationcorrosion/rusting/oxidation others????others????
Physical PropertiesPhysical Properties
characteristics it possesses by itself characteristics it possesses by itself (in and of itself)(in and of itself)
““personal” traitspersonal” traits
response to energyresponse to energy
Physical PropertiesPhysical Properties
colorcolor sizesize texturetexture melting pointmelting point boiling pointboiling point solubilitysolubility
lusterluster densitydensity magnetismmagnetism odorodor viscosityviscosity crystalline crystalline
structurestructure
Physical PropertiesPhysical Properties Electrical Electrical propertiesproperties
conductor or insulatorconductor or insulator
Optical Optical properties – response to lightproperties – response to light index of index of refraction refraction – bending of light– bending of light transparenttransparent – light passes through – light passes through translucenttranslucent – some light passes through but – some light passes through but
no distinct imageno distinct image opaqueopaque – no light passes through – no light passes through
Physical PropertiesPhysical Properties
ThermalThermal properties – response to properties – response to heatheat
conductivityconductivity
specific heat – how much energy it takes specific heat – how much energy it takes to change temperatureto change temperature
thermal expansion – thermal expansion – example: iron wire example: iron wire demodemo
Mechanical PropertiesMechanical Properties
subgroup of physicalsubgroup of physical
response to force or stressresponse to force or stress forceforce – a push or pull – a push or pull
stressstress – force causing a deformation or – force causing a deformation or distortion (force per unit area)distortion (force per unit area)
Mechanical PropertiesMechanical PropertiesExamplesExamples
workabilityworkability malleabilitymalleability – can be flattened – can be flattened ductilityductility – can be drawn into wire – can be drawn into wire
(stretched), bent, or extruded(stretched), bent, or extruded
Mechanical PropertiesMechanical PropertiesExamplesExamples
brittlenessbrittleness breaks instead of deforming when stress breaks instead of deforming when stress
is appliedis applied
hardnesshardness resistance to denting or scratchingresistance to denting or scratching
http://www.youtube.com/watch?v=i1x-vJ85sBAhttp://www.youtube.com/watch?v=i1x-vJ85sBA
http://www.youtube.com/watch?v=eF5943tlbBshttp://www.youtube.com/watch?v=eF5943tlbBs
Mechanical PropertiesMechanical PropertiesExamplesExamples
elasticityelasticity ability to return to original shape after being ability to return to original shape after being
deformed by stress deformed by stress rubber ball or piece of elasticrubber ball or piece of elastic http://www.flixxy.com/golf-ball-slow-motion.htm
plasticityplasticity retains new shape after being deformed by retains new shape after being deformed by
stress stress wet clay ball or piece of saran wrapwet clay ball or piece of saran wrap
Mechanical PropertiesMechanical PropertiesExamplesExamples
toughnesstoughness ability to absorb energy ability to absorb energy resistance to fractureresistance to fracture http://www.steeluniversity.org/content/html/eng/charpy-test.asphttp://www.steeluniversity.org/content/html/eng/charpy-test.asp http://www.youtube.com/watch?v=a_aOlh6dSA8http://www.youtube.com/watch?v=a_aOlh6dSA8 http://www.youtube.com/watch?v=N276_xjl04g&feature=related http://www.youtube.com/watch?v=N276_xjl04g&feature=related
strengthstrength resistance to distortion by stress or forceresistance to distortion by stress or force several types: tensile, compressive, torsional, several types: tensile, compressive, torsional,
bending, shearbending, shear
Types of Types of Stresses/ForcesStresses/Forces
TensionTension pullingpulling examples:examples: tug-of-war, slingshottug-of-war, slingshot
CompressionCompression pushing together or squeezingpushing together or squeezing examples:examples: bed springs, can crusher, bench visebed springs, can crusher, bench vise
Types of Types of Stresses/ForcesStresses/Forces
TorsionTorsion twistingtwisting example: wringing out a wet towelexample: wringing out a wet towel
ShearShear opposite forces not lined upopposite forces not lined up examples: scissors, pin in a wagon tongue, examples: scissors, pin in a wagon tongue,
shear pinshear pin
Stress-Strain CurveStress-Strain Curve
StressStress cause cause force causing a deformation or distortionforce causing a deformation or distortion
Strain Strain effecteffect change caused by stress (ex. change caused by stress (ex.
elongation)elongation)
stress
strain
Ceramic orglass
metal
polymer
straight line = elastic regioncurved line = plastic region
City of MaterialsCity of Materials
http://dev.sancsoft.com/http://dev.sancsoft.com/educationasm/asmeducation.html educationasm/asmeducation.html
http://www.cityofmaterials.comhttp://www.cityofmaterials.com
Tensile testsTensile tests
http://www.youtube.com/watch?v=SzJ4YLbMF-Y&NR=1http://www.youtube.com/watch?v=SzJ4YLbMF-Y&NR=1 http://www.youtube.com/watch?http://www.youtube.com/watch?
v=W5A8gU37wGg&feature=relatedv=W5A8gU37wGg&feature=related Close up of tensile strain and break Close up of tensile strain and break
General Classes of General Classes of MaterialsMaterials
PolymersPolymers
CeramicsCeramics
CompositesComposites
Metals and AlloysMetals and Alloys
Metals and AlloysMetals and Alloys
Wood and Wood Wood and Wood ProductsProducts
DensityDensity
DensityDensity
how much “stuff” per how much how much “stuff” per how much “space”“space” stuff = matter (mass)stuff = matter (mass) space = volumespace = volume per = divideper = divide
Density = Density =
Unit = g/cmUnit = g/cm3 3 or g/mL or g/mL
massmass
volumevolume
MassMass amount of matteramount of matter measured with a balancemeasured with a balance unit = grams (g)unit = grams (g)
MassMass
VolumeVolume
Volume Volume how much space it occupieshow much space it occupies liquidsliquids
measured with a graduated cylindermeasured with a graduated cylinder unit = mLunit = mL
solidssolids regular-shapedregular-shaped
find the dimensions and use an equationfind the dimensions and use an equation irregular-shapedirregular-shaped
use the water displacement methoduse the water displacement method units = cmunits = cm33
1cm1cm33 = 1 mL = 1 mL
Variations in DensityVariations in Density
Density varies with change in temperature Density varies with change in temperature of a substance.of a substance. warmer is usually less densewarmer is usually less dense warm objects/substances usually expandwarm objects/substances usually expand same mass, more volumesame mass, more volume
Density does Density does notnot vary with a change in vary with a change in amount of a substanceamount of a substance Which is more dense:Which is more dense:
a gram of aluminum or a kilogram of aluminum?a gram of aluminum or a kilogram of aluminum?
Calculating Density of an Calculating Density of an Unknown SolidUnknown Solid
Procedure:Procedure:
You must do two cylinders, two cubes, and You must do two cylinders, two cubes, and one irregular shaped solid.one irregular shaped solid.
Make a table to record all data.Make a table to record all data.
1. Record the identifying letter of the sample.1. Record the identifying letter of the sample.
2. Measure and record the mass.2. Measure and record the mass. Use the entire sample for the irregular shaped Use the entire sample for the irregular shaped
solid.solid.
Calculating Density of an Unknown Calculating Density of an Unknown SolidSolid
3. Measure and record the dimensions of the 3. Measure and record the dimensions of the regular shaped solids.regular shaped solids.
Use the digital calipers and convert mm to cm Use the digital calipers and convert mm to cm (move decimal point one place to the left). (move decimal point one place to the left).
cube: length, width, and heightcube: length, width, and height cylinder: diameter and heightcylinder: diameter and height
4. Use water displacement to find the 4. Use water displacement to find the volume of the irregular shaped solidvolume of the irregular shaped solid
Record it in your data table.Record it in your data table. Use the entire sample.Use the entire sample. Describe the basic procedure for water Describe the basic procedure for water
displacement in your journal.displacement in your journal.
Calculating Density of an Unknown Calculating Density of an Unknown SolidSolid
5. Calculate and record the volume for 5. Calculate and record the volume for the regular shaped solids using the the regular shaped solids using the following formulas:following formulas:
cube: volume = length x width x heightcube: volume = length x width x height
cylinder: volume = πrcylinder: volume = πr22hh radius = diameter/2radius = diameter/2 π = 3.14π = 3.14
Calculating Density of an Unknown Calculating Density of an Unknown SolidSolid
6. Calculate and record the density of 6. Calculate and record the density of the five materials.the five materials. Be sure to include units.Be sure to include units. Record the formula for density in your Record the formula for density in your
journal.journal.
7. Use the list of densities to identify 7. Use the list of densities to identify each material and record your each material and record your choice.choice.