Presentation on theme: "Warm-up Josie wants to find out if beeswax candles burn faster than regular candles. What is the independent variable? The dependent variable? Max wants."— Presentation transcript:
1 Warm-upJosie wants to find out if beeswax candles burn faster than regular candles. What is the independent variable? The dependent variable?Max wants to test the speed of a motor with a 9 volt battery and a 24 volt battery. What is the independent variable? The dependent variable?
2 Heat (SOL 7) Chapter 2, pages 50-56 (change of state) and Chapter 4 (kinetic theory of matter, temperature scales, thermal expansion, energy flow, convection, conduction, radiation)
3 HEAT!! And change of state The speed at which atoms move is called?Kinetic Energy!
4 If the pressure stays the same, Everything expands when heated and shrinks (contracts) when cooled ExceptWater!!!Water expands when it cools!!!!
5 Kinetic Theory of Matter Matter is made up of particles which are in continual random motion.
6 Temperature Measures Motion Motion of atoms and molecules affects an object’s state of matter (solid, liquid, gas) and its temperature.Fast motion = high temperature; Slow motion= low temperaturecold liquidhot liquid
7 Temperature Temperature is the Measurement of how fast molecules are moving.Adaptive curriculum temperature
8 Celsius – the SI unit for temperature 0 is freezing point of water (at sea level)100 is boiling point of water (at sea level)Do I have to know this? YES!!!
9 Farenheit Freezing is 32 degrees Boiling is 212 degrees. Do I have to know this?NO!!!
10 Kelvin Freezing point is 273 Boiling point is 373 Why these crazy numbers? Because in the Kelvin scale 0 = absolute zero. The temperature at which all matter turns solid. (freezes) and motion stops.Do I have to memorize these numbers? NO!!!!
11 No Motion = Not Possible Show PSA – Heat and Temperature .mov
12 No Motion = Not Possible Absolute Zero is a theoretical point where all molecular motion is stopped.It is -273 degrees CelsiusIt is at 0 degrees KelvinIt is at -456 degrees Fahrenheit.Show PSA – Heat and Temperature .mov
16 Moving atoms move atoms The transfer of this motion of atoms/molecules is called HEAT.This energy flows from where it is HOT to where it is NOT. Even cold things have heat energy!What is an example of heat going from where it’s hot to where it’s not?Adaptive Curriculum – Heat Conduction– (Aka – Pans on a Stove)Adaptive Curriculum – Heat Transfer – Heat Conduction of Different materials ( AKA - Get Aliens out of Ice)Do Lab – Physics Quest – Melting Hershey Kisses by placing them on different types of metal sticks and place in hot water.Lab – Physics Quest – Convection of heat using birthday candles to make small pie tin move on a pencil.Link = Bill Nye Heaticeheat
18 Matter Can Exist in Different States: ENERGY, Pressure & Volume PHET change of state
19 Properties of WaterWater coheres, which means water molecules are atrracted to each other. Why? Because one end of a water molecule has a positive chargeAnd the other end has a negative charge so there is magnetic attraction.
20 Coheres – sticks to itself Causing Surface Tension
21 THAT’S A FACT ----Water is the only substance that can be found as a solid, liquid and gas at normal surface temperatures on Earth.
22 Change of State When a substance changes state (solid, liquid, gas) it’s identity does not change and the process can be reversed.All three of thesePictures are ofiron in differentStates.
23 Warm-upWhat holds more heat – a glass of water or a lake (if they are at the same temperature)What is the name for the process by which a liquid becomes a solid?What is the SI unit of measurement for temperature?In the heating curve on the right, what is the boiling point temperature?What letter is the melting point?What letter represents a gas?What is the freezing point?What is the condensation point?What is the difference betweenConduction and convection?10. What is absolute zero?
24 Change of State: Heating matter ADD ENERGY (heating) and atoms can speed up enough to change state:Melting – solid changes to liquid.The temperature at which this happens is the “melting point”.
31 Matter Brainpop-States of Matter Freeze popcorn kernals in butter. Place into a a beaker on a hot plate. Warning – hot popcorn will fly.Ask – what state of matter is this? SolidWhen heated- what state is it turning into?Why does the graph show a flat line?? (when changing phase all energy goes toward making the change and moving atoms further apart. The temp. does not change during a phase change.)What happens to the butter when the kernals pop – it changes to a gas.How would you describe the energy change when turning to a gas?Have kids eat the popcorn and write in science journal about phase changes and energy.Adaptive Curriculum-Melting and Boiling Points – Heating CurvesHeating Curves Activity. Print off Student Worksheet at the bottom.Teacher’s Domain Video Heat Fusion of Water -
32 Sublimation – solid turns to a gas (no liquid phase)
33 Change of State (Cooling) REMOVE ENERGY (cooling) and atoms move slower, this can cause a change of stateCondensation – a gas becomes a liquid.Freezing – A liquid becomes a solid.
37 What Determines the State of Matter? Energy of the Atoms (measured as Temperature)Pressure on the AtomsVolume – The amount of space the atoms are given.Have kids fold a paper hot dog style and put PTV on it. Ask, what happens if I increase the pressure…volume decreases.What is temperature goes up?Click Pressure to go to classzone and explore PTV interactions.Use pressure pullers to boil water.
38 Thermal ExpansionWhen an object is heated, its atoms move faster and take up more space so the size of the object expandsWater is the exception. It gets smaller when heated and larger when frozen
40 Warm-upWhat do you think holds more heat? Which would be easier to increase or decrease the heat of? Why?Which of theseheats upFaster? WhyRubber tireCopper Cube
41 Heat . . .Large substances hold more heat than smaller substances and it’s more difficult to change their heat.Specific heat – The specific heat is the amount of heat per unit mass required to raise the temperature by one degree Celsius. What substances do you think have a high specific heat? A low specific heat?
42 Atom Motion is Transferred Classzone - Conduction, Convection, RadiationCan also add Conduction, Convection, Radiation Rap Song.