Chemical and Physical Properties of Matter 1 Matter

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Chemical and Physical Properties of Matter 1

Chemical and Physical Properties of Matter 1

Matter • Matter is • Different matter has different 2

Matter • Matter is • Different matter has different 2

Physical Properties • A physical property • Some physical properties are • Ex –

Physical Properties • A physical property • Some physical properties are • Ex – Will your books fit into you backpack? You are using the physical property of volume. 3

Physical Properties • Thermal conductivity – • State of Matter – • Density –

Physical Properties • Thermal conductivity – • State of Matter – • Density – 4

Physical Properties • Solubility – • Ductility – • Malleability – 5

Physical Properties • Solubility – • Ductility – • Malleability – 5

Physical Changes • A physical change • Ex. A piece of silver is pounded

Physical Changes • A physical change • Ex. A piece of silver is pounded and molded into a heart-shaped pendent. (it is still silver) • Ex. – changing from a liquid to a solid (or any phase change) • Ex. – crushing an Aluminum can. It is still aluminum, just the shape has changed. • Ex – Sawdust – it is still wood – only in smaller pieces. 6

Chemical Properties • Chemical properties • Chemical changes occur when • Ex. – burning

Chemical Properties • Chemical properties • Chemical changes occur when • Ex. – burning wood, tarnishing, and rusting 7

Chemical Properties • Flammability – • Reactivity – • Chemical reactions involve two main

Chemical Properties • Flammability – • Reactivity – • Chemical reactions involve two main kinds of changes that you can observe – 8

Physical Properties vs. Chemical Properties • __________– physical property being changed is shape •

Physical Properties vs. Chemical Properties • __________– physical property being changed is shape • __________– chemical property being changed is composition (iron is reacting with oxygen to make iron oxide - rust) • __________– physical change of state • __________– chemical change – it is not alcohol any more. 9

How do I know that a chemical change is taking place? • There will

How do I know that a chemical change is taking place? • There will be a change in odor and/or color, heat will be either absorbed or released, the substance will bubble or fizz, light or sound may be given off. • Ex. – – – 10

Changes in Energy • As matter changes, ___________. A change in energy occurs during

Changes in Energy • As matter changes, ___________. A change in energy occurs during a chemical reaction. • An endothermic reaction • Many endothermic reactions occur when heat is constantly added. (Ex: egg frying) In other words…they need energy to keep going. 11

Changes in Energy • An exothermic reaction • After an exothermic reaction, the products

Changes in Energy • An exothermic reaction • After an exothermic reaction, the products have _______________. (Ex: the burning of fuel) • The reaction between fuel and oxygen in an airplane engine releases energy, mostly in the form of heat. The expansion and movement of the gases out of the plane exerts a force that moves the plane forward. 12

Can physical and chemical changes be reversed? • Physical changes are _________. You can

Can physical and chemical changes be reversed? • Physical changes are _________. You can melt ice and then freeze it again. • Chemical changed are__________. When a firework explodes it would be almost impossible to put the materials back together. 13