The Properties of MatterThe Properties of Matter

Section 2Section 2

Physical PropertiesPhysical Properties

Physical PropertiesPhysical Properties

Can be observed or measured Can be observed or measured without changing the substance’s without changing the substance’s identityidentity

Color, odor, shape & volume are Color, odor, shape & volume are physical propertiesphysical properties

Useful Physical Properties in ScienceUseful Physical Properties in Science

Thermal conductivity – how fast a Thermal conductivity – how fast a substance substance transfers heattransfers heat

Solubility – ability of one substance to Solubility – ability of one substance to dissolve in dissolve in another another substancesubstance

Useful Physical Properties in Science Useful Physical Properties in Science (con’t.)(con’t.)

State – physical form in which a substance State – physical form in which a substance existsexists

Ductility – ability of a substance to be Ductility – ability of a substance to be pulled into pulled into a wire a wire

Useful Physical Properties in Science Useful Physical Properties in Science (con’t.)(con’t.)

Malleability – ability of a substance to be Malleability – ability of a substance to be pounded or rolled into pounded or rolled into

thin sheetsthin sheets

Density – the amount of mass per unit Density – the amount of mass per unit volumevolume

DensityDensity

Describes the relationship between the Describes the relationship between the amount of mass and the volume of a amount of mass and the volume of a substancesubstance

Every pure substance has its own unique Every pure substance has its own unique density.density.

Can be used to identify unknown Can be used to identify unknown substancessubstances

Solving for DensitySolving for Density

Measure the object’s mass.Measure the object’s mass.

Measure the object’s volume.Measure the object’s volume.

Use the formula density = Use the formula density = massmass

volumevolume

Density UnitsDensity Units

Combination of the mass unit and volume unitCombination of the mass unit and volume unit

Mass is usually measured in grams or kilograms.Mass is usually measured in grams or kilograms.

Volume is usually measured in milliliters or liters.Volume is usually measured in milliliters or liters.

Solid volume is measured in cubic centimeters.Solid volume is measured in cubic centimeters.

Density units are written g/mL and read “grams Density units are written g/mL and read “grams per milliliter.”per milliliter.”

Sample Density ProblemSample Density Problem

What is the density of an object whose What is the density of an object whose mass is 25 g and whose volume is 10 cmmass is 25 g and whose volume is 10 cm33??

Write the formula: Write the formula: D = D = mm VV

Substitute the values: Substitute the values: D = D = 25g25g 10 cm10 cm

Solve: Solve: D = 2.5 g/cmD = 2.5 g/cm33

Other Useful FormulasOther Useful Formulas

To solve for mass: m = D x VTo solve for mass: m = D x V

To solve for volume: V = To solve for volume: V = mm

DD