1. Physical Science 513 - Unit 2 2.2 Properties of Matter

2. Lesson Objectives Unit 2 5.Explain the difference between a physical and a chemical property of matter 6.Identify common physical properties of matter and give examples

3. Properties of Matter Chemical Property Can only be observed if the identity of the substance is changed; a chemical reaction occurs Ex. Flammability Ex. Reactivity with water

4. Properties of Matter Physical Property Can be observed without the identity of the substance being changed Ex. Mass, density, phase

5. Properties of Matter A cube of ice is melting. Why is melting a physical property rather than a chemical property? At the melting point, the ice (water in the solid state) is becoming liquid water. The identity of the substance has not changed. It is water before melting and after melting.

6. Properties of Matter A sample of hematite

7. Physical Properties of Matter Diamond How easily matter can be scratched Hardness Glass How easily matter shatters upon impact Brittleness Sandpaper vs. Cotton How matter feels to the touch Texture Glossy photo paper How matter reflects light Luster The color of the matter Color Density of steel paper clip = density of large steel beam Comparison of mass to volume; how tightly the atoms or molecules are packed; D= m/v Density Example Description/Definition Property Gemstones

8. Properties of Matter KEVLAR fiber Measure of how much pulling or tension a material can withstand before breaking Tensile Strength Copper Ability to let heat or electricity pass through Conductivity Copper Ability to be drawn into a thin wire Ductility Aluminum Ability to be pounded into a thin sheet Malleability Rubber band Measure of a solid’s ability to be stretched and then return to its original size Elasticity Hematite streak is blood-red The color a mineral leaves behind when rubbed across an unglazed tile (does not always match the external color of the mineral). Streak ExampleDescription/DefinitionProperty

9. Properties of Matter Metal pan Light cannot pass through matter Opacity (opaque) Frosted window Light goes through matter but is diffused so objects on other side are not clearly visible Translucency Air Light passes through matter almost completely Transparency Sugar, Salt Ability of matter to dissolve in water. Solubility ExampleDescription/Definition Property of Matter