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Science 7 Unit C

Heat and Temperature

Topics 1-3

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Pg. 184 - 209Topic 1: Using Energy from Heat

Uses for Heat1) Name 3 ways that we use heat:

i: ____________________________________________

ii: ____________________________________________

iii: ____________________________________________

2) Think about the evolution of how we use heat to cook. Name three processes.

3) How is your house being heated?

• Since the beginning of time people have used _______ ________ to cook their food and keep them warm.

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Name:

• What and how we used thermal energy has __________ a great deal over the years. For example _____ and ________ ranges have replaced __________ stoves.

• People’s lifestyle _________, and __________ drive the new improvements in technology. New ____________ technology in electric blankets help keep your feet warm, while not scorching the rest of your body.

Activity – answer the following questions using your own knowledge1) What options are available if you want to dry your hair?

2) Does this represent a need or a want? Why?

3) Why do you think we invented drying machines when we can leave it out to dry on a line outside?

Putting Energy to WorkWhat to DoWhen do you use thermal energy? Imagine that it is an average, mid-winter school day. In what situations do you use or need thermal energy (heat)? Read the following sentences and complete each with a word from the list below.

Words to use:Boiler, hair dryer, furnace, kettle, steamed up, hot water heater, body heat, heatIn the situations described above, several sources of thermal energy that humans use are mentioned or described. Use them to fill in the chart.

1. When you get up in the morning, the house is warm. The ____________________ kept the house warm all night and will keep it warm during the day.

2. In the bathroom you notice a light bulb is burnt out. The bulbs that are lit are hot and give off ____________________ in addition to light. The burnt-out bulb is still cold.

3. The ____________________ makes and stores hot water for your home. The hot shower soon makes the bathroom ____________________.

4. Hot air from the ____________________ evaporates the water from your hair.

5. You need some porridge to keep you warm today. The ____________________ boils water for the instant porridge.

6. The coat, gloves, boots and hat you wear help keep your ____________________ where you need it…in and around you.

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7. As you walk into the school, you feel a blast of hot air. Thank goodness the custodian keeps the ____________________ well maintained!

Thermal Energy Sources How Humans use this Heat Source1.

2.

3.

4.

5.

6.

7.

Do Investigation 3-A, p. 189 (Ask 5 people, survey results due next class)Your Data:Respondent Source of

energy to heat building

Source of energy to cook

Method Why chosen

Class Summary Data:Source for heating

Class Totals Source for cooking

Class totals

Analysis:1.

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2.

Topic 2: Measuring TemperatureUse the chart below to complete the activity: Boiling Hot, Freezing Cold (pg. 198)

Description Everyday, very hot or very cold

Temperature

Temperature of lava from Hawaiian volcanoes Very hot

Temperature of ocean currents off Canada’s east coast Everyday

Temperature of currents off Canada’s west coast Everyday

World record coldest air temperature Very cold

Comfortable room temperature Everyday

Body temperature of a budgie bird Everyday

Temperature where the Space Shuttle flies in orbit Very cold

Temperature of a candle flame Very hot

Comfortable temperature for heat-loving bacteria Very hot

Normal human body temperature Everyday

Temperature of ice cream Everyday

Oven temperature for baking bread Very hot

Temperature of food in a freezer Everyday

Temperature of the interior of the Sun Very hot

Temperature of hot tea or coffee Very hot

Temperature of boiling water at sea level Very hot

Temperature of a slush of pure water and ice Everyday

Temperature of the surface of the sun Very hot

A practical everyday definition of temperature: A number that tells you _________________________________________________.People often estimate temperature by:

- ___________________- _______________________________________________

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Estimating temperatures with your eyes and skin is not always _____________ or __________________.

Did you know?The hottest temperature ever recorded in Canada was _____________________.The coldest temperature ever recorded in Canada was _____________________.

Activity: Page 193 Baffle Your Skin

Background Information: There are specialized cells within our skin that can detect changes in temperature, but sometimes, these sensors can be fooled!

Question: How does our skin detect thermal energy?

Hypothesis:

Observations:

Analysis:

1. What was the manipulated variable in this experiment?

2. What was the responding variable?

3. Were your hands able to detect the actual temperature of the water? Explain.

4. What do you think your hands were able to detect?

5. What is the difference between heat and temperature?

6. Why do you think your senses were fooled in this investigation?

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Thermometers

Senses can be easily fooled, but _____________ are more reliable.Thermometers: is a mechanical or electrical device used for __________________________________________________.- _______________ invented his air thermometer around 1600

AD.- Liquid thermometers were invented around 1700 AD.

The air and liquid thermometers of the 1600 and 1700’s were missing an essential element of today’s thermometers: A _________.

Activity: Look at figure 3.4 on page 193 and answer the following question.What is the major difference between the thermometer shown in the photo and modern thermometers?

Temperature Scales

Scale: A series of _____________________________________ that are marked and numbered for use in measurement (e.g. Centimetres, litres, or celsius).

- Having a scale allows scientists to measure temperatures more ______________.

- _____________________, or evenly spaced lines, allow you to __________________________________________.

Celsius (C) Scale: The most common measuring scale for __________ _____________.

- Developed by Anders Celcius (1742) - In the Celsius scale the __________________ is the unit of

temperature. - Celsius based his standardized scale on the __________________

_____________.- He assigned the ________________________, at sea level, a value of

100oC - He assigned the __________________________, at sea level, a value

of 0oC7

- He then divided the space between the two values into evenly spaced ___________________.

- Finally he extended these degrees above 100 and below zero.

The two fixed temperatures that Celsius chose (0oC and 100oC) are extremely useful because they can be used for ____________________________________.

Calibrate: determine and check the ________________________ _________________________________.

Calibration must be done at sea level using extremely _____________ since these factors can ________________ the boiling and freezing points of water.____________________ also affects the boiling point and freezing point of water.

- Water boils at _____________ temperatures under ___________ pressures

- Extremely ______________ pressure, such as under glaciers or under skate blades, cause ice to flow or even melt at ____________________.

- Under low pressure water will boil __________________ it reaches 100oC. Water boils at _________ on the top of Mt. Everest.

The Kelvin Scale:- As scientists were developing theories to help explain the

behaviour of gases at different temperatures, they realized that they needed a temperature scale that started at the _________________________ _____________ or _________________.

- This new scale was named _________________ after William Thomson who was given the title Lord Kelvin.

• The units of temperature on the Kelvin scale are NOT degrees but are simply called _____________.

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• No one has ever been able to cool anything down to absolute zero, but scientists ____________ that the temperature is _________.

Convert from one scale to another: - Celsius to Kelvin :

The following are common temperatures you should know:- Comfortable room temperature: ________- Normal human body temperature: _________- Temperature of boiling water at Sea Level: _______- Temperature at which water freezes at sea level: ________

The Laboratory Thermometer

Question: What is a laboratory thermometer and how does it work?

1. Write the scale on this thermometer (calibrate).

2. Using a ruler and printing in lower case letters, put these labels on the right hand side of the diagram.

□ liquid (coloured alcohol)□ bore (fine opening through which the liquid moves)□ thick glass□ bulb (storage space for liquid)□ thin glass□ the scale

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Celsius (°C) Kelvins (Kelvins)0

0100

□ freezing point of water□ boiling point of water□ lowest temperature shown on

this thermometer (state what it is)□ highest temperature shown on

this thermometer (state what it is)□ average room temperature□ average normal body temperature

3. What temperature is this thermometer measuring at this time?

4. Hold your hand around the middle of the thermometer for at least one minute. Describe what happens to the temperature.

5. Hold your hand around the bulb of the thermometer for at least one minute. Describe what happens to the temperature.

6. Place 400 mL of cold tap water into a beaker. Put the thermometer into the beaker, being careful not to touch the sides and bottom of the beaker. Read the temperature at eye level and record it. ___________

7. Repeat procedure #6 using hot tap water. Read the temperature at eye level and record it. ___________

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Questions:1. Why is the glass for the bulb of the thermometer thinner than the glass which

makes up the rest of the thermometer?

2. How many Celsius degrees are there between the freezing point of water and the boiling point of water? ___________

3. What is the highest temperature of liquid that you could put this thermometer into? Explain why.

4. What is the lowest temperature of liquid that you could put this thermometer into? Explain why.

5. Mercury is no longer used in student laboratory thermometers. Instead, alcohol which is dyed red, is used. Explain why.

How Different Thermometers Work

Think about it:The first thermometer was built in 1593 by Galileo, a famous Italian Scientist. Since then, other scientists have experimented with different designs. Today’s thermometers might look different from the early models, but the theory behind them has not changed.

What to do:Use the space provided, or a separate page, to answer the following questions. Use Figures 3.4A, B and C in your textbook (page 193-4) to help you.

1. How are an air thermometer and a liquid thermometer different?________________________________________________________________________________________________________________________________________________

2. (a) What features do a liquid thermometer and a lab thermometer have in common?____________________________________________________________________________

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____________________________________________________________________

(b) How are they different?________________________________________________________________________________________________________________________________________________

3. (a) What change occurs in the liquid inside a thermometer when the thermometer is placed in something hot?________________________________________________________________________________________________________________________________________________

(b) What change occurs in the air thermometer when the thermometer is placed in hot air?________________________________________________________________________________________________________________________________________________

4. What is the advantage of having the liquid move up a narrow bore?________________________________________________________________________________________________________________________________________________

5. A clinical thermometer is used to measure the temperature of a human. (a) The scale is calibrated in degrees Celsius. It shows a range from 35C to 42C. Why is a

clinical thermometer made to measure only temperatures in this narrow range?________________________________________________________________________________________________________________________________________________

(b) The glass stem is designed to act as a magnifying glass. Why is the stem designed this way?

________________________________________________________________________________________________________________________________________________

(c) The glass around the bulb is relatively thin. Why is the glass so thin?________________________________________________________________________________________________________________________________________________

(d) Why is the bore narrow directly above the bulb?_______________________________________________________________________________________________________________________________________________

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Types of ThermometersThermometers have been developed to suit almost every purpose, from extreme cold to incredible heat.

5 types:- ____________________________- ____________________________- ____________________________- ____________________________- ____________________________

All thermometers have 3 common components:- Sensor: made of material that reacts to _____________ in certain

aspects in the ______________, such as temperature- Signal: Information about temperature, such as an ___________- Responder: a pointer, light or other instrument that ___________

the signal in some way.

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Other Temperature Sensing Devices

A) Thermocouple:Wires made of _______________________ that are twisted together.

- When the wires are __________________ they produce an_____________________.

- The ___________ of current depends on the ____________________ of the wires.

Thermocouples can be used for:- Measuring _______________ temperatures (so

high that ordinary lab thermometers fail) - Turn a switch or valve ___________________- We cannot use it to measure _______ temperatures accurately

B) Bimetallic Strip The bimetallic strip is formed with two different metals joined firmly together.

- When they are heated up, one metal _____________ more than the other causing the strip to __________ more tightly

- When the strip cools, one metal ____________ more than the other, causing the coil to partially ______________.

- Movements of the bimetallic strip can operate a type of ____________ _______________.

Bimetallic strips are commonly used to control __________________ ___________________________________ and other devices.

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C) The Recording Thermometer (___________________)

- In one type, a bimetallic strip moves a long __________ with a ________ attached to the end. This pen records ____________ on a slowly turning drum (1 turn/7 days).

D) The Infrared Thermogram

Objects are _____________________ with special films or detected by electronic sensors.

- Anything that is warmer than absolute zero gives off ________________ _____________________

IR is a type of radiation similar to ____________- The colour of the image indicates the ____________________.

Red and white colours indicate the ________________________. Blue colours indicate the _____________________________.

Infrared thermometers are used for:- ______________________- ______________________

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- Finding out where ________________________________ - ________________________________

E) Liquid Chrystal Thermometer

Some kinds of crystals turn certain ____________ at different _______________.

- These crystals are put into strips that are used to take your temperature by simply ______________________________.

Temperature, Heat and Energy

What to DoAnswer the following questions in the space provided.

1. Complete the word search by finding all the words listed below. Circle the words as you find them. An example is done for you.

ABSOLUTE ZERO COLD HOT LIQUID SCALEAIR ENERGY JOULE MEASURING TEMPERATURECALIBRATE FAHRENHEIT KELVIN PARTICLES THERMALCALORIC FLUID GLOBAL WARMING ICE POLLUTION THERMOMETERCELSIUS HEAT ZERO

M A B S O L U T E Z E R OE I A E T A R B I L A C TN R C C O L D U R Y A R EO F O P A R T I C L E S MI A E E L A C S O T G R PT H L H T O H R E C N K EU R U E O L I M C D I E RL E O A O C O E I Z R L AL N J T F M L U E U U V TO H R L R S Q R E D S I UP E U E I I O A L C A N RO I H U L C H Y G R E N ED T S T H E R M A L M O LG N I M R A W L A B O L G

2. Now that you have found all the words, there are 24 letters left uncircled. Work your way across each row in the word search, starting with the top row, and find these letters. Write them in the spaces below to complete the sentence about thermometers.

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The liquid commonly used in a thermometer is either__ __ __ __ __ __ __ __ ____ __ __ __ __ __ __ __ __ __ __ __ __ __ __ .

Topic 2 Review – page 2011). Suppose that you were present on the hottest day ever reported in Canada.

a). What would your body temperature have been?

b). If the air temperature had dropped by 5˚C, would you have felt warm or cold?

2). Describe how a thermostat controls the temperature in a building

3). What might be the advantages and disadvantages of using a thermocouple instead of a regular lab thermometer?

4). Many household appliances, such as irons, are heated electrically. They usually contain a thermostat that switches electricity on and off to keep the appliance at a constant temperature. Think of at least three examples of other appliances that might use thermostats to switch electricity on and off.

5). Choose the most appropriate temperature-measuring instrument to use in each situation below. In each case, explain your choice.

a). controlling an electric frying pan

b). making long-term temperature records at a weather office

c). detecting small forest fires before they spread

d). monitoring temperatures inside a furnace

e). checking trains for overheating wheel bearings as they pass by

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f). studying temperature changes inside a building over a 24 hour period

6) If you were boiling some water to make hot chocolate in different places around the world, where (sea level or high elevations) would it take the least amount of time (assuming you use the same heat source)? And where would it be the hottest?

Topic 1 and 2 Practice Quiz

1. This type of thermal energy source can be used to cook food, but they are hard to control, dangerous and messy.A. Open firesB. Fireplaces

C. Pioneer wood burning stoveD. Modern gas stove

2. A technology that has replaced boiling water over an open campfire gives us warning when the water has boiled. This technology isA. A micro-sensing digital boilerB. A solar powered water heater

C. An electric kettleD. A hot water heater

3. Choose the technology that you would need so that you could heat a large room in your house and maintain a constant comfortable temperature in that room.A. A gas furnaceB. A wood-burning fireplace

C. An electric fireplaceD. A digital thermostat

4. Estimating temperature is something we do automatically. Touching something to see how hot or cold it is, is one technique that we use. Another is toA. Use a thermometerB. Look at the moving particles

C. Observe the colourD. Use the back of your hand

5. The earliest thermometers contained a glass bottle with a long glass tube for the liquid to rise and fall. An important part that was missing was theA. Type of liquid that senses temperature changeB. Type of glass that doesn’t expandC. The calibrated scale of relative temperaturesD. The protective stoppers to prevent the liquid from escaping

6. Pressure affects the boiling point and freezing point of water. Extreme pressure under a glacier can cause the ice to flow or even melt at temperaturesA. Above 0˚CB. Below 0˚C

C. Around room temperatureD. Above boiling temperature

7. Absolute zero is A. -273.15 FB. -273.15˚C

C. -2.73.15 KD. 0 ˚C

8. A material, which is affected by changes in some feature of the environment, such as temperature, isA. CircuitB. Sensor

C. SignalD. Responder

9. A thermometer that would be good for measuring extremely high temperatures is a

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A. Bimetallic stripB. Laboratory thermometer

C. ThermocoupleD. Thermograph

10. The hottest temperature ever recorded in Canada wasA. 0KB. 25K

C. 45˚CD. 60˚C

Topic 2 Graphic Organizer Review

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THERMOMETERS

Definition –

Define: Sensor -

Signal -

Responder -

Temperature Scales

Types of Thermometers

Kelvin:

Celsius:

Thermocouple:

Bimetallic Strip:

Recording Thermometer:

Topic 3: Particle Theory, Temperature and Thermal Energy

Particle Model of Matter The three (plus one) most important ideas of the model are:

1. All substances are made of _________ particles too small to be seen.

2. The particles are always in __________ – ______________, ____________, and (in liquids and gases) ___________ from place to place.

3. The particles have _____________ between them.4. The motion of particles _______________ when the temperature

increases. The motion of the particles ________________ when the temperature decreases.

• It is not easy to ___________ the particle model because:1. Particles of matter are too __________ to observe clearly.2. They can only be observed in ____________ groups.3. Some particles are moving ____________ and some are moving

______________ than average.

Do Find out activity p. 202

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Celsius:

Infrared Thermogram:

1) Name the state(s) in which a material:

a) has a fixed shape

b) takes the shape of its container

c) always fills whatever container it is in

2) Name the state(s) in which the particles are

a) far apart from each other

b) relatively close together

c) free to move around

d) held in fixed positions• Temperature: __________________________________________________

________________________________________________________________________________________________. OR

• Temperature: ___________________________________________________________________________________________________________________________________________

Remember the fourth point in the particle model:The motion of particles ___________ when the temperature increases. The motion of the particles ___________ when the temperature decreases.Computer Simulation: Answer the following questions and complete the diagram after watching the simulation.

What happens to the particles in a substance when it’s heated up?

What happens to the particles in a substance when it’s cooled? 21

Activity: Use the space below to complete Questions 1-3 and 1-2 from the “Detect a Connection” activity on pg. 203.

Rule:___________ indicates the ___________of the particles in a substance.

What is energy? Energy is the measurement of the ______________________

____________________________, (cause physical or chemical change). We use _________________ in honor of James Joule, to measure

energy. Whenever something happens, scientists know that energy is being

transferred.

Law of Conservation of EnergyEnergy cannot be ____________ or ______________. It can only be transformed from one __________ to another or passed from one ___________ to another.

The temperature of a substance is directly linked to the kinetic energy of the particles in that substance.

A _________ substance has a _________ level of energy than that of a __________ substance.

Activity: Read the following statements and decide if they are true or false, using pg. 204-207 to help you.

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True or False Statement

Energy is a substance

We can not create energy

Energy can be transformed from one form to another

Energy can not be passed from one object to another

Energy has a mass

Energy does not take up space

Energy describes a quality or condition

We can destroy energy

Think of the movement of particles. When there is more energy, is the substance hotter or colder?

TOPIC 3What is Energy?

BLM 3-8VOCABULARY CHECK

Goal • Develop a complete understanding of the concept of energy.

What to do:Read about energy in your text and then complete the following chart. Compare the examples and place a check mark in the appropriate column. The first example is done for you.

Statement More Energy Less EnergyA fully charged battery (a new battery) checkA used (uncharged) battery checkA candleA campfireSchool P.A. systemA rock concert’s speaker systemA ping-pong ball after it is hitA golf ball after it is hit

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Read the statements below and mark it as either True (T) or False (F).___ 1. Energy can be transferred.___ 2. Particles (mass) can be moved (transferred).___ 3. Energy has mass.___ 4. Particles have mass.___ 5. Energy makes particles move.___ 6. Moving particles have energy.___ 7. Energy can flow on its own.___ 8. Particles can start to move on their own (by themselves).___ 9. Heat energy flows from colder to hotter areas.___ 10. Energy from burning gas in a hot air balloon transfers to the air around it.___ 11. An ice cube has no energy.___ 12. An iceberg has more energy than an ice cube.

Thermal energyThe ________________ of a substance is directly linked to the ________________ of the particles in that substance.

When a substance __________________________ energy, its particles will move __________ and with more freedom. We perceive this acceleration of particles as ________________

Thermal energy: The energy generated by the ____________ or___________ of particles OR the _________ __________ __________of all the particles in a substance.

• Hot air balloons, ovens, and hot tubs are all examples of devices that are designed to release and transfer thermal energy.

HeatHeat is the __________________________________ from one substance to another.

The temperature of a substance is directly linked to the _____________ _________ in that substance.

When a substance ___________ energy, its particles will move _______ and with more freedom.

We feel this acceleration of particles as _____________. 24

Heat is always transferred from a __________ substance, which has ___________ thermal energy, to a ________ substance that has ___________ thermal energy.

There is a connection between thermal energy and temperature.

Heating anything increases the ________ energy of all its particles; however, the __________ energy, temperature, of the particles may increase a little or a lot.

The temperature change of the substance depends on the ____________ of particles you are heating.

Cooling a substance occurs when a colder substance _____________ thermal energy from a warmer substance, thus reducing the average motion of the particles in the ___________ substance.

Temperature change, again, depends on the amount of material, as well as on the change in thermal energy.

What energy is and is not….

Energy is not a ____________!

It does not have ______ and it does not take up ____________.

Energy describes a ________ or condition.

Energy is a property or quality of an object or substance that gives it the ability to ______, do __________, or cause ____________.

Explain how an ice cube can make a glass of lemonade colder?

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Would a single ice cub have the same effectiveness on a bathtub of hot water?

Topic 3 Review (pg. 208)1). List the 4 points of the particle model of matter.

2). Why is it so hard to test the particle model to see if it’s correct?

3). Name an important discovery or idea contributed by each of these scientists:- James Joule

- Anders Celsius

- Lord Kelvin

4). Provide three reasons why thermal energy is different from temperature.

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Temperature vs Thermal Energy

Think About It Temperature is a measure of the average energy of the particles in a material. Thermal energy is the total energy of all the particles in the material.

What to DoReview the definitions of temperature and thermal energy given above.Answer the following questions in the space provided.

1. (a) Why is the temperature of the little bit of soup in the spoon the same as the temperature of the larger volume of soup in the bowl?

(b) Although their temperatures are the same, the bowl of soup has more thermal energy than the spoonful of soup. Explain why.

2. Suppose you have the following four beakers of water.

Use the particle model to describe what happens when the hot water in the first or second beaker is poured into one of the beakers of cold water.

(a) Suppose you poured the hot water in the first beaker into one beaker of cold water. Then you poured the hot water in the second beaker into the other beaker of cold water. Which mixture would have a greater temperature?

(b) Would your answer in part (b) be different if the temperature of the ¼ L of hot water was much higher than the temperature of the ½ L of hot water?

(c) On which two factors does the final temperature of a mixture of hot and cold water depend?27

Topic 3 Practice Quiz

1. The Particle Model of Matter helps to explain ideas about thermal energy. This model includes each of the following points EXCEPT

A. All substances are made up of tiny particles that are too small to seeB. The particles are always in motionC. The particles increase their energy output when they collideD. The particles have spaces between them

2. Another important idea about temperature and the particle theory is that the motion of particles increases when the temperature increases. Which statement below is also correct?

A. As the motion of particles decreases the temperature remains the sameB. As the temperature decreases the motion of the particles increasesC. As the motion of the particles decreases the temperature decreasesD. As the temperature increases the motion of the particles decreases

3. Energy is the measure of something’s ability to do work. Which of the following has the most thermal energy?

A. A dead batteryB. A melted SlurpeeC. A cup of hot coffeeD. A swimming pool

4. Which of the following energy transfers would be correct?

A. Thermal energy in a hot drink is transferred to cold handsB. Thermal energy is transferred from a room to a heater, so it can be heatedC. An ice cube loses thermal energy when it melts in hot lemonadeD. Thermal energy is lost by a match when it is lit

5. Which of the following statements about energy is a correct scientific description of what energy is?

A. Energy is a substance that can be transferred B. The mass of energy can be measured using a precise instrumentC. Energy fills the space with highly charged tiny particlesD. Energy is a description of a quality or condition

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Topic 1-3 ReviewQuiz on _______________

Key Terms Thermometers Scales Particle model of matter Energy Celsius scaleSensor Signal Responder Thermal energy Temperature Kelvin Scale

Matching Use a straight line to match and join the name of the scientist in column B with the scientist’s important discovery or idea in column A.

A B

1. investigated the connection between energy and Anders Celsiustemperature changes

2. developed the temperature scale used throughout Lord Kelvinthe world today

3. used graphs to predict the coldest possible James Jouletemperature: absolute zero

4. developed the caloric fluid theory Antoine Lavoisier

True or False In the space provided, indicate whether each statement is true (T) or false (F).

5. A slow-moving snail has low energy. 6. Estimating temperatures with your eyes or skin is always very reliable. 7. Substances with high thermal energy have fast-moving particles. 8. Energy has no mass and does not take up space. 9. The temperature of absolute zero is 0°F. 10. Using very precise instruments, scientists can measure thermal energy directly

from the motion of the particles.

Short Answers Answer the following questions in the space provided.

11. Explain and contrast how an air thermometer and a liquid thermometer work.

12. (a) Name the two temperature scales used today.

(b) Which scale is used for scientific measurements, especially those involving gases or very cold temperatures?

13. Describe how changes in temperature affect the liquid inside a thermometer.

14. (a) What does “absolute zero” represent?

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(b) What is the temperature of “absolute zero” (in Celsius and Kelvin)?

15. What are the temperatures of the following:(a) normal human body temperature

(b) comfortable room temperature

16. Write the steps for calibrating a thermometer in degrees Celsius (°C).

17. Name one specialized thermometer that is discussed in your textbook. Explain how it works.

18. a) Define energy.

(b) How are energy descriptions useful to scientists?

(c) What unit is used to measure energy?

Long Answers19. Explain how a cup of very hot tea can have less thermal energy than a kettle of lukewarm water.

20. Scientists cannot test the theory on which the particle model is based. Tell why not, and describe how they have developed a definition of temperature.

21. (a) Define thermal energy.

(b) How is thermal energy different from temperature?

(c) Which two factors affect the amount of thermal energy in an object?

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