Properties and Changes in Matter Chapter 20 Glencoe Science

Physical Property A characteristic that you can observe without changing or trying to change the composition of the substance.

Physical Property How something looks, smells, sounds, or tastes are all examples of physical properties.

Physical Properties You can detect many physical properties with your senses.

Mass Mass is a measurement of how much matter an object contains.

Weight Weight is a measurement of force. Weight depends on the mass of the object and on gravity. No matter where you are in the universe your mass never changes, but your weight can.

Density Density measures the amount of mass in a given volume. Density = mass/volume D=m/v

Solubility Solubility is the ability of one substance to dissolve into another substance.

Melting Point The temperature at which a solid changes into a liquid is called its melting point.

Boiling Point The temperature at which a liquid changes into a gas is called its boiling point.

Magnetism Magnetism is a physical property.

Chemical Property A chemical property is a characteristic that cannot be observed without altering the substance.

Chemical Properties Examples of chemical properties: Flammability, rusting, reacting with substances like acids

Physical Changes A physical change is one in which the form or appearance of matter changes, but not its composition.

Changing State Vaporization is the process by which matter changes from a liquid state to a gas.

Changing State Condensation is the process where a gas changes into a liquid.

Changing State Sublimation is the process in which a solid changes directly into a gas. Ex: dry ice

Changing State Deposition is the process in which a gas changes into a solid.

Chemical Changes Chemical changes occur when substances are changed into different substances.

Clues to Chemical Changes Color change is an example of a chemical change.

Clues to Chemical Changes Another sign of a chemical change is the release or gain of energy by an object.

Clues to Chemical Changes The change in odor is a clue to a chemical change.

Signs of Chemical Changes The production of bubbles is a sign that a chemical change has taken place.

Clues to Chemical Changes Another clue to a chemical change is the formation of a solid.

Chemical Changes The substances produced during a chemical change cannot be changed back into the original substances by physical means.

Chemical vs. Physical During a physical change the composition of the substance does not change, but during a chemical change the composition of the substance does change. Chemical change Physical change

Conservation of Mass Law of conservation of mass states that mass is neither created nor destroyed. As a result the mass of the substances before a physical or chemical change is equal to the mass of the substances present after the change.

Chemical vs. Physical Chemical and Physical Changes Game