Physical and
Chemical Properties
Physical Property• A characteristic of a substance that does not
involve a chemical change, such as density, color or hardness
• Color, shape, odor, weight, volume, texture, state and density
• Apple: don’t have to change it to see that it is round and red
General Physical Properties• Size
• Shape
• Color
•Smell
•Weight or Mass
•Volume
Specific Physical Properties• Thermal Conductivity• Solubility• Ductility• Magnetism • State• Density• Malleability
Thermal Conductivity
• The rate at which a substance transfers heat.
Example: Plastic Foam is a poor conductor
Solubility
• The ability of a substance to dissolve in another substance
Example: Flavored drink mix dissolves in water
Ductility• The ability of a substance to be
pulled into a wire
Electrical Conductivity: describes how freely charges can move in a material. Copper is
often used to make wiring because it is ductile and it has a high electrical conductivity.
Magnetism• The property of some materials
to attract iron or objects containing iron.
Example: lodestone is a naturally magnetic rock
State• The physical form in which a substance exists, such as a solid,
liquid or gas.
Example: Ice is water in the solid state
Density• The mass per unit volume of a
substance.
Example: Lead is very dense, so it makes a good sinker for a fishing line
Malleability• The ability of a substance to be
rolled or pounded into thin sheets.
Example: Aluminum can be rolled into sheets to make foil
Chemical Property
Describes a substance’s ability to participate in chemical reactions
Example: When wood is burned, ash and smoke are created. The new substances have very different properties than the original wood
Flammability• The ability of a substance
to burn.
Example: Wood has the property of flammability. However, ash and
smoke can’t burn, so the have the chemical property of
nonflammability.
Reactivity• The ability of two or more
substances to combine and form one or more new substances
• Example: Car Example*Iron on this car has the chemical property of reactivity with oxygen. When iron is exposed to oxygen, it rusts.*The bumper of this car still looks new because it is coated with chromium, which has a chemical property of nonreactivity with oxygen.
Comparing Chemical and Physical Properties
• Physical properties are easy to observe. You can measure the density or the
hardness without changing anything.
• Chemical properties are harder to observe. You can only see that wood is flammable
when it is actually burning. BUT that piece of wood is still considered flammable even
when it’s not burning.