DENSITY A PHYSICAL INTENSIVE PROPERTY
DENSITY • Density is the mass of a substance that occupies a given volume. • The SI standard unit of volume is the cubic meter (m3), it is more practical to express the density of solids and liquids in g/cm3. • Since gases are less dense than solids or liquids their densities are usually given in g/dm3.
Units for Density • The units used to express density are derived units. • Mass is a physical extensive property expressed in grams. • Volume is a physical extensive property expressed in cubic centimeters. • Density is a physical intensive property.
The Equation for Density • d = m/V • Given: mass and volume • Find: density • Factor: d = m/V (and any other factors as needed for unit conversion)
Type 1 • What is the density of a hydrochloric acid solution that has a mass of 17.84 g and occupies a volume of 15.00 cm3? • Given: m = 17.84 g V = 15.00 cm3 • Find: density • Factor: d = m/V
Density as a Conversion Factor • Density can also be used as a conversion factor between mass and volume. If the density of a substance is 8.92 g/cm3 then the volume of 1cm3 is known: 1cm3 = 8.92 g
Type II • Given: mass • Find: Volume • Factor: density written as a factor: • 1cm3 = __________ g ( and other factors needed for unit conversions )
Type III • Given: volume • Find: mass • Factor: density written as a factor: 1 cm3 = ________ g (and any other factors needed for unit conversions)