Presentation on theme: "Notes 2—Properties of Matter Mr. Pruett Monday, August 17, 2015."— Presentation transcript:
Notes 2—Properties of Matter Mr. Pruett Monday, August 17, 2015
There are four phases of matter: solid liquid gas (plasma— not discussed in this unit )
Properties of Matter 1. Hardness 2. Elasticity 3. Brittleness 4. Malleability 5. Density 6. Viscosity 7. Buoyancy
1.Hardness—Measures a solid’s resistance to scratching 2. Elasticity—measure of a solid’s ability to be stretched and then return to its original size 3. Brittleness—Measures a material’s tendency to shatter upon impact 4. Malleability—Measures a solid’s ability to be pounded into thin sheets
Density–property that describes the relationship between mass and volume. (how close together the molecules are) Solids Liquids Gas Molecules close together Molecules spread out further Molecules spread far apart
Mass Volume Density = Density of Water = 1 gram 1milliliter
If an object with a density of less than 1g/mL is placed in the water, it will _______. float
If an object with a density of greater than 1g/mL is placed in the water, it will _____. sink
Buoyancy Archimedes was an ancient Greek scientist who discovered that floating objects are supported by an upward force called buoyancy.Archimedes was an ancient Greek scientist who discovered that floating objects are supported by an upward force called buoyancy. Buoyancy—measure of the upward force a fluid exerts on an object.Buoyancy—measure of the upward force a fluid exerts on an object. Buoyant force is equal to the weight of the liquid that the force displaces.Buoyant force is equal to the weight of the liquid that the force displaces.
Viscosity—measure of a material’s resistance to flow. Not all fluids flow quickly Viscosity
Some fluids move slowly. They have a high viscosity. It is very viscous. Syrup pours slowly.
Some fluids move quickly. They have a low viscosity. Water pours quickly. It is less viscous.
Element—pure substance that cannot be separated into simpler substance by physical or chemical means.
Compounds Pure substance composed of two or more different elements joined by chemical bonds. –Made of elements in a specific ratio that is always the same –Can only be separated by chemical means, not physically
Mixtures A combination of two or more pure substances that are not chemically combined. substances held together by physical forces Each item retains its properties in the mixture They can be separated physically
Mixtures Heterogeneous—a mixture in which every sample might have a different composition. Homogeneous—a mixture in which every sample has the same composition.
Can you identify the following? Review before the pictures… An element contains just one type of atom. A compound contains two or more different atoms joined together. A mixture contains two or more different substances that are only physically joined together, not chemically.