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Do Now:. Drop off your stuff and head over to Banneker for a mini-lab. Do Now:. What are the states of matter? What processes exist that change states of matter?. Do Now (2/22/12):.
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Do Now: • Drop off your stuff and head over to Banneker for a mini-lab
Do Now: • What are the states of matter? • What processes exist that change states of matter?
Do Now (2/22/12): • Please come in quietly and clear your desks of everything except your notecard, writing utensil, and calculator. Thanks!
Do Now: • What is a phase change? • Do we need heat to cause a phase change? • Is there a temperature change during a phase change?
Phase Changes 2/25/11
Brainstorm: • What are the states of matter? • What processes exist that change states of matter?
States of Matter • Three states of matter: Solid, liquid, and gas • Phase change: any transition between two states of matter
Fusion • Transition from a liquid to a solid state; occurs at the melting point (0˚C for water)
Vaporization • Transition from a liquid to a gaseous state; occurs at the boiling point (100˚C for water)
Melting • Transition from a solid to a liquid state; occurs at the melting point (0˚C for water)
Condensation • Transition from a gaseous state to a liquid state; occurs at the boiling point (100˚C for water)
Evaporation • The random escape of molecules from the surface of a liquid – NOT the same thing as vaporization, which occurs only at 100˚C
Temperature changes • THERE ARE NO TEMPERATURE CHANGES DURING A PHASE CHANGE!!!!!!!
Do Now (2/23/12): • List and describe two of the phase changes we discussed yesterday.
Heat of fusion • The amount of heat required to melt 1 kg of a substance • For ice: • Heat required to melt a substance • To freeze a substance, take this amount of heat away
Example: Fusion • How much heat is required to freeze 50 kg of ice at 0˚C?
Heat of vaporization • The amount of heat required to boil 1 kg of a substance • For water: • Heat required to boil a substance • To condense a substance, take this amount of heat away
Example: Vaporization • How much heat is required to boil 50 kg of water at 100˚C?
Phase and Temperature Changes • Please flip to the front of your phase change sheet
Classwork: • Finish one example on your phase change worksheet • Once you have completed that, you may work on your homework.
Classwork: • Finish the front of your phase change worksheet • Once you have completed that, you may begin working on your homework.
Do Now (2/24/12): • How much heat must be added to turn 2 kg of ice at -10˚C to ice at 0˚C? • How much heat must be added to turn that ice into liquid water at 0˚C? • What is the total heat required? • *hint – use the back of your phase changes worksheet! • Happy Friday!!!
Heat Diagrams • Use the rest of class to work with your ONE PARTNER on the assignment “Heat Diagrams.” Include all work, calculations, and answers, as well as diagrams.
Do Now (2/27/12): • How much heat must be added to turn 4 kg of water at 10˚C to water vapor at 120˚C? • Draw a heat diagram and set up the equations.
Next Mousetrap Car Deadline • Monday, March 5: Bring in or email proof (photo or video) that you have a vehicle that can roll 1 m. It does not need to have a mousetrap yet.
Practice: • Finish Heat Diagram activity – make sure ALL heats are calculated!!! • Work on Homework
Classwork: • Finish Heat Diagram activity – make sure ALL heats are calculated!!! • Work on Phase Changes worksheet A or B • QUIZ TOMORROW ON PHASE CHANGES AND HEAT DIAGRAMS!!!!!!
Do Now: • 4 kj of heat are added to a 2 kg block of ice at 0˚C. How much ice will melt?
Do Now (2/28/12): A physicist plans to change 0.1 kg of ice at -12 C into 0.1 kg of water at 44C. • What is the heat required to bring the ice to its melting point? • What is the heat required to melt the ice? • What is the heat required to raise the temperature of the melted ice to 44˚C?
Quiz: • QUIZ TOMORROW: PHASE CHANGES • You may bring a notecard! Specific heats and heats of fusion and vaporization will be provided.
Quiz Review: • Please use the rest of class to work on the paper “Phase Changes Classwork.” You may work with your peers, but your work MUST BE YOUR OWN!!! We will check at the end of class • In #2: change “0” to “100” Thx!
Do Now (2/29/12): • How much heat is released to turn 93 kg of steam at 100˚C to water at 100˚C? • Happy Leap Day!
Do Now (3/1/12): • Suppose you were to add ice to a cup of room temperature water. Then, you added the same amount of ice water (water at 0˚C) to a second cup of room temperature water. • What would happen eventually? • In which cup would it happen faster?
Do Now (3/2/12): • You are working in a lab with Bunsen burners and hot materials. What are some good safety precautions and guidelines you should keep in mind as you work?
Do Now (3/5/12): • Of the two labs we did last week, which did you like better? Why?
Agenda: • Finish lab data • Work on vocab review • Check vocab review • Test review tomorrow!!!! • Test: Thermodynamics on WEDNESDAY!!! • Specific heat lab due Wednesday
Do NowA: • 20 kj of heat are removed from 1.5 kg of ice initially at -29 ˚C. What is its new temperature?