The Physical Properties of Matter

What is a physical property of matter? A property that can be observed or measured without changing the identity of that matter Ex: Color, odor, shape, size, etc.

Thermal Conductivity Definition: The ability to transfer thermal energy (heat) to something else Example: Coffee in a special cup to prevent heat transfer to our hands

Malleability Definition: The ability to be pounded into thin sheets Example: Aluminum can be pounded flat to make aluminum foil

Ductility Definition: The ability to be drawn into thin wires Example: Copper is used to make wires

Example: Alka-seltzer dissolves in water or sugar dissolves in coffee Solubility Definition: The ability for one substance to dissolve into another substance

Density Definition: Mass per unit volume ( the amount of matter in a given space) unit: g/mL or g/cm 3

More information about density... Most substances have a unique density: Water = 1.00 g/mL Gold = g/mL Lead = 11.3 g/mL lead is used for fishing weight because it is more dense than water Density < 1 - The object will float in water Density > 1 – The object will sink in water

Factors Affecting Density…. Size (amount) doesn’t matter Temperature affects density  Heat causes particles to move faster, spread out, and take up more space = more VOLUME  If volume changes, then density changes

Formula

Practice Problem # g of sample Volume is 5 cm 3 Density = ? Mass 96.5 g Volume 5 cm 3 Density = g/cm 3 (gold)

Practice Problem # 2 20 cm 3 of gold What is its mass? Density of gold is g/cm 3 M = D x V g/cm 3 x 20cm 3 = g

Rectangular Object # 1 Volume = 48 cm 3 (4 x 6 x 2) Mass = 24 g Density = ? Mass= 24g Volume48 cm 3 = 0.5 g/cm 3 6 cm 4cm 2cm

Rectangular Object # 2 Volume = 12 cm 3 (2 x 3 x 2) Mass = 24 g Density = ? Mass= 24g Volume12 cm 3 = 2 g/cm 3 3 cm 2cm

More EXAMPLES - Physical size, shape, state, freezing point, boiling point, melting point Viscosity - The resistance of a liquid to flowing. –Low viscosity  water –High viscosity  honey

More EXAMPLES - Physical Brittleness = Can be easily broken or crushed into smaller pieces Example: sea shells Hardness = Resistance to being crushed. Example: rock Luster = The way light interacts with the surface