Properties of Matter

Objectives How can properties used to describe matter be classified? Why do all samples of a substance have the same intensive properties? What are three states of matter? How can physical changes be classified?

Important Vocabulary Mass Volume Extensive property Intensive property Substance Physical property Solid Liquid Gas Vapor Physical change

Describing Matter Begins with observation Properties used to describe matter can be classified as extensive or intensive

Extensive Properties Are properties that depends on the amount of matter in a sample Extensive properties include: mass & volume

Intensive Properties Are properties that depends on the type of matter in a sample Intensive properties include: hardness, melting point, boiling point and color

Mass Is the amount of matter within an object Mass is usually measured in grams or kilograms We use balances to measure mass

Weight Is not the same thing as mass Weight is the measure of the gravitational force upon an object Weight can change with location, whereas mass cannot It is measured in Newtons Weight is proportional to an object’s mass

Volume Is the space an object occupies The method of finding the volume of an object varies How do we find the volume of a lab table? How about a bottle of water? What if the object is a gas?

Identifying Substances Substances are matter with uniform and definite compositions Elements like gold and copper are pure substances Every sample of a given substance has identical intensive properties because every sample has the same composition

Physical Properties Are properties of a substance that can be observed or measured without changing the composition of the substance Examples of physical properties: ◦ State ◦ Melting point ◦ Boiling point ◦ Density ◦ Color ◦ Hardness ◦ Conductivity ◦ Malleability

Physical States of Matter All matter is made of particles The type and arrangement of the particles within the matter determine its state Matter usually exists in 1 of 3 states of matter ◦ Solid ◦ Liquid ◦ Gas  What is the 4 th state of matter & where is it found?

Microscopic Views

Properties of the Physical States Solids: have fixed volume and shape, rigid structure, incompressible, and vibrate slightly Liquids: have fixed volume but not shape, has the ability to flow, almost incompressible, and takes the shape of its container Gases: have neither fixed volume nor shape, particles are spaced out, compressible, and will fill any container they occupy ◦ Vapor describes the gaseous state of a normally solid or liquid at room temperature

Physical Changes Are changes in which the identity of the substances doesn’t change However, the arrangement, location, and speed of the particles within the substance may change Examples?

Mini Lab Tomorrow Read p.22