TemperatureTemperatureWe often associate We often associate

temperature with how __________ temperature with how __________ something feelssomething feels

Hot and Cold are terms that Hot and Cold are terms that can be ___________________can be ___________________

The same object can feel warm The same object can feel warm or cool depending on the or cool depending on the properties of the object and the properties of the object and the condition of your bodycondition of your body

HotHot ColdCold Luke warmLuke warm

Moving Energy Moving Energy Changes Temp.Changes Temp.

Consider an oven- turn Consider an oven- turn the dial on and heat is the dial on and heat is delivered as energy delivered as energy flows. When the dial is flows. When the dial is off, energy stops flowing off, energy stops flowing and temperature coolsand temperature cools

TemperatureTemperatureTemperature is proportional to the Temperature is proportional to the

_____________ of atoms and molecules._____________ of atoms and molecules.To understand temperature, think To understand temperature, think

of atoms & molecules and of atoms & molecules and _____________. With more heat, atoms _____________. With more heat, atoms move more, have more KE. When move more, have more KE. When heat is removed, the energy of heat is removed, the energy of theses moving atoms/ molecules is theses moving atoms/ molecules is called _________________.called _________________.

Internal EnergyInternal Energy

The energy of substance The energy of substance due to the ______________ of due to the ______________ of its component particles its component particles and equal to the total and equal to the total energy of those particlesenergy of those particles

Thermal EquilibriumThermal Equilibrium

The state in which two The state in which two bodies in physical contact bodies in physical contact with each other have with each other have ____________ temperatures____________ temperatures

COLD COLD WATERWATER

Warm Warm BeveragBeverag

ee

In time both In time both liquids will have liquids will have

equal equal temperaturestemperatures

You can not find __________________ You can not find __________________ until thermal equilibrium is reacheduntil thermal equilibrium is reached

The temperature of the liquid in the The temperature of the liquid in the thermometer must _______________ thermometer must _______________ the temperature of the object being the temperature of the object being measured. This must happen in measured. This must happen in order to know the temperatureorder to know the temperature

““You don’t read a thermometer You don’t read a thermometer until the mercury/ alcohol has until the mercury/ alcohol has stopped rising/ falling”stopped rising/ falling”

Thermal ExpansionThermal ExpansionThings get Things get __________________ they they EXPANDEXPANDThings get Things get __________________ they they CONTRACTCONTRACT

– Concrete bridgesConcrete bridges– Rail Road RailsRail Road Rails– Power LinesPower Lines– Hot glass – cold water – cracksHot glass – cold water – cracks

This is True for all solids, liquids and This is True for all solids, liquids and gasses (some more than others)gasses (some more than others)

Anomaly of WaterAnomaly of Water

A strange thing A strange thing happens to water happens to water between between _____________: as it gets _____________: as it gets colder, it EXPANDS- colder, it EXPANDS- GOOD NEWS FOR FISH!!GOOD NEWS FOR FISH!!

ICE 0ICE 0°°CC

11°°22°°

33°°

44°°

ThermometersThermometersA glass tube containing a A glass tube containing a

thin column of mercury, thin column of mercury, colored alcohol, or colored alcohol, or colored mineral spiritscolored mineral spirits

When heated, Liquid When heated, Liquid __________________________________

To calibrate thermometers To calibrate thermometers and to set a standard for and to set a standard for temperature we have temperature we have chosen water to be our chosen water to be our bench mark.- Not just any bench mark.- Not just any water – water – ______ ______ __________________________________________________

Calibrating ThermometersCalibrating Thermometers

What About FahrenheitWhat About Fahrenheit

We must convert with the We must convert with the following formulas:following formulas:– To find To find °F°F °°F = 9/5(F = 9/5(°C)°C) + + 3232

– To Find To Find °°CC °C = 5/9(°F - 32)°C = 5/9(°F - 32)

With With °F and °C, often times you °F and °C, often times you get negative numbers; This is get negative numbers; This is because many things are colder because many things are colder than our standard “________”than our standard “________”

To eliminate neg. values for To eliminate neg. values for temperature, the ___________ was temperature, the ___________ was usedused– 0 Kelvin is as cold as anything 0 Kelvin is as cold as anything

can getcan get– From 0 K, you can only go upFrom 0 K, you can only go up

Kelvin ScaleKelvin Scale

Kelvin ScaleKelvin ScaleThe best thermal lab on The best thermal lab on

record has reached record has reached 0.0000001 K0.0000001 K

At 0K, the theory states At 0K, the theory states that ___________ would that ___________ would cease to vibratecease to vibrate

Kelvin ConversionsKelvin Conversions

To find K To find K Kelvin temp = °C + 273.15Kelvin temp = °C + 273.15

To find °C To find °C °C = Kelvin Temp - 273.15 °C = Kelvin Temp - 273.15

Practice Problems 10A 1-5 pg. 3Practice Problems 10A 1-5 pg. 3

HOMEWORK 2, 4, 5, 7, 9, 10 pg. 12HOMEWORK 2, 4, 5, 7, 9, 10 pg. 12

Section 10-2 Section 10-2 Defining HeatDefining Heat

Read Read andand

UnderstandUnderstand

Defining HeatDefining HeatHeat:Heat:

– Flow of _________Flow of _________– Moves in one direction, from Moves in one direction, from

____ to ____________ to ________– Symbol _____Symbol _____– Has units for energy (Joule) Has units for energy (Joule)

(calorie, kilocalorie, dietary (calorie, kilocalorie, dietary calorie, Btu, therm)calorie, Btu, therm)

Specific Heat CapacitySpecific Heat Capacity

This is the amount of energy required This is the amount of energy required to change the temperature of 1Kg of to change the temperature of 1Kg of a substance by a substance by °C°C

Cp = Q/ mCp = Q/ mΔT ΔT

Q = m CP ΔTQ = m CP ΔT

Q = Heat (Joules)Q = Heat (Joules)

m = mass (Kg)m = mass (Kg)

Cp = Specific Heat (J/KgCp = Specific Heat (J/Kg°C)°C)

ΔT = change in temp (ΔT = change in temp (°C)°C)

Table 10.4 Table 10.4 (pg. 7)(pg. 7)

Substances take differing Substances take differing amounts of energy to amounts of energy to heat upheat up–Water heats up _________Water heats up _________–Lead heats up ________Lead heats up ________

CalorimetryCalorimetryTo determine specific heat To determine specific heat

capacity we do calorimetrycapacity we do calorimetryFor calorimetry always For calorimetry always

remember: remember: Energy absorbed = Energy releasedEnergy absorbed = Energy released

QQwaterwater = Q = Qxx

CCppww M Mww ΔTΔTw w = Cp = Cpxx M Mxx ΔT ΔTxx

Practice Problems:

Practice Problems:

10c Pg.810c Pg.8

7, 6, 5, 47, 6, 5, 4

Homework:

Homework:

Pg.12 -13Pg.12 -13

13, 14, 16, 21, 22, 28

13, 14, 16, 21, 22, 28

Latent HeatLatent Heat______________________________

Latent heat is the heat Latent heat is the heat needed to change the needed to change the physical ______ of a physical ______ of a substance (at constant substance (at constant pressure)pressure)SOLIDSOLID LIQUILIQUI

DDGASGAS

Latent HeatLatent Heat Ice chest: mostly ice - little water (temp 0Ice chest: mostly ice - little water (temp 0°°C)C) Ice chest: mostly water - little ice (temp 0Ice chest: mostly water - little ice (temp 0°°C)C)Heat was added to melt the ice but temp didn’t Heat was added to melt the ice but temp didn’t

changechange Boiling water: 100Boiling water: 100°C- doesn’t get hotter until °C- doesn’t get hotter until

all water is gone, Even though heat is all water is gone, Even though heat is continually added the water stays at continually added the water stays at 100100°C°C

These examples show latent heatThese examples show latent heatAll substances have this hidden heat (gold, All substances have this hidden heat (gold,

lead, aluminum, water, copper, ect.)lead, aluminum, water, copper, ect.)

2 Types of Latent Heat2 Types of Latent Heat Both have the same units of heat (J) Both have the same units of heat (J)

and symbol Qand symbol Q ________________________________: the energy per unit : the energy per unit

mass transferred in order to change a mass transferred in order to change a substance from substance from liquidliquid to to solidsolid or or solidsolid to to liquidliquid

________________________________: the energy per unit : the energy per unit mass transferred in order to change a mass transferred in order to change a substance from substance from liquidliquid to to vaporvapor or or vaporvapor to to liquidliquid

Formula for Latent HeatFormula for Latent Heat

Q = mLQ = mLf/vf/v

Q = HeatQ = Heatm = massm = mass

LLvv = heat of vaporization = heat of vaporization

LLff = heat of fusion = heat of fusionLook at table 10-6Look at table 10-6

OVERHEADOVERHEAD

Heat FlowHeat Flow________________________________________: this is how : this is how

heat flows through a substance. heat flows through a substance. Some materials conduct heat Some materials conduct heat well. others are very poor well. others are very poor (insulators)(insulators)

Generally, metals are good Generally, metals are good conductors of heat. Asbestos, conductors of heat. Asbestos, cork, ceramic, cardboard,& cork, ceramic, cardboard,& fiberglass are good insulatorsfiberglass are good insulators

Heat Moves in 3 WaysHeat Moves in 3 Ways______________________: heat moving through : heat moving through

2 objects that touch each other2 objects that touch each other______________________: heating by : heating by

movement of fluids(liquids and movement of fluids(liquids and gases). Involves displacement gases). Involves displacement of cold matter by hotof cold matter by hot

Heat Movement Cont…Heat Movement Cont…

________________________________: : electromagnetic rays carry electromagnetic rays carry heat from everything above 0 heat from everything above 0 Kelvin in the form of waves. Kelvin in the form of waves. Nom medium is needed for Nom medium is needed for this- occurs in the vacuum of this- occurs in the vacuum of space. Also, near a campfirespace. Also, near a campfire

ThermosThermosKeeps hot things hot, Keeps hot things hot, cold things cold because cold things cold because it minimizes heat flowit minimizes heat flow

OVERHEADOVERHEAD

Clothes & climateClothes & climate– Eskimo- ParkaEskimo- Parka– Arabian - Desert DressArabian - Desert Dress

Section ReviewSection Review

HOMEWORK:HOMEWORK:

29, 32, 33 - 3929, 32, 33 - 39