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Starter Question. Day 3: Identify as Chemical or Physical change: Methane & Air = Fire Epson Salt & Water = Dissolve Crushing glass Iron rusting. Starter Questions. Day 4: According to the graph, What phase is the water between minutes 5-20?
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Starter Question • Day 3: • Identify as Chemical or Physical change: • Methane & Air = Fire • Epson Salt & Water = Dissolve • Crushing glass • Iron rusting
Starter Questions Day 4: • According to the graph, What phase is the water between minutes 5-20? • What is the water experiencing between minutes 20-30? 20 Min, 100○ 5 Min, 0○
Starter Questions Day 5: Use the following reactions to answer the questions: • Iodine + Starch Purple • Iodine + Baking Soda Dissolves • Which reaction is physical? • Which reaction is chemical?
Solid Ice Liquid Water Steam (gas) Evaporating / Boiling Melting
Phases & States of Matter • All phases are dependant upon the amount of thermal energy the substance has in relation to the strength of the bonds between molecules in the substance.
Solids • Low Energy • Not enough energy to break the bonds between molecules • High Bond Strength • Definite Shape • Definite Volume “Ice” Demo: People holding on to each other – moving & holding hands
Liquids • Medium Energy • Some bonds broken – but they keep reforming. • Medium Bond Strength • No Definite Shape • Definite Volume “Water”
Gasses “Vapor” • High Thermal Energy • Enough energy to break the bonds • Low Bond Strength • No Definite Shape • No Definite Volume
Energy of the Phases: Q: What is the ONLY real difference between each phase? A: The amount of energy the molecules have!
Change from phase to phase: Solid Liquid Q: What do we have to do to change phases? Gas A: Increase/ Decrease the energy (temperature measures this)
Change from phase to phase: Melting Solid Freezing Evaporating Liquid Condensing Q: As a substance experiences a phase change, what are the processes called? Gas A: Melting, Freezing, Evaporating, Condensing
Difference between boiling & evaporation • Evaporation • Water vaporizes only at the surface.
Difference between boiling & evaporation • Boiling: • Water vaporizes both at the surface and within the liquid.
Difference between boiling & evaporation • Boiling: • Point at which a substance boils is called boiling point. • Used to help identify unknown substances
Difference between boiling & evaporation • Boiling Point: • Boiling Point depends upon the air pressure • The lower the pressure, the less energy needed for particles of the liquid to escape into the air.
Change from phase to phase: Melting Solid Freezing Evaporating Liquid Condensing Q: When we change the phase, have we made a new substance? Gas A: NO! IT IS STILL WATER! ***No change in the substance = Physical Change!
Class Lab Boiling Water Lab • Fill up beaker with ice ~ 200 mL • Fill up beaker with water ~ 100mL • Start readings when temp stops dropping (1min) • Start flame • Stop after it Boils for 3 minutes
Candle Lab Carbon Dioxide & Water Fire is the Chemical Reaction Wax Vapor Liquid Wax Wax Vapor Solid Wax Demo: Burner & 3x5 card
Basic Temperature Graph Changing Phase (melting, freezing, boiling, evaporating, condensing) Temperature Change Temperature Phase (Solid, Liquid, Gas) Time
Graphing Phases & Phase Change Vapor Vapor Condensing Evaporation /Boiling Liquid Liquid Melting Freezing Solid Solid
Graphing Phases & Phase Change Gas Phase Liquid Phase Solid Phase
Boiling Point is Dependant upon Air Pressure Demo: Have 1 kid plow through two groups of kids – one small other large • Boiling Point: