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Grade 7 Science

Unit 2: Heat

Chapter 4: Temperature describes how hot

or cold an object is.

Name:

Section #:

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Temperature…

How does temperature affect your daily life?

Why do you feel warm playing outside on a cold winter’s day?

**Try at home- Baffle your skin**

Complete the activity sheet included in your work book at home and submit to your teacher by

Monday, December 5th.

Complete the Activity sheet 4-1A in class on page 111 (see work booklet page 7)

Standard Temperatures (0C)

Human Body Temperature

Boiling Point of Water

Freezing Point of Water

Comfortable Room Temperature

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Measuring Temperatures

Early Thermoscopes…

Galileo Early Liquid Thermometer

Uses?

How it works…

Diagram

A Demo… Building a Thermoscope

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Temperature Scales

Scales are necessary for temperatures to be and

Three commonly used scales are:

Fahrenheit Celsius Kelvin

Developed by?

Points of interest…

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Measuring Devices

Uses Diagram

Liquid-in-glass thermometer

Thermocouple

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Resistance thermometer (digital thermometers)

Thermostat (bimetallic strip)

Infrared Thermometer (thermogram)

A Demo… Using a Bimetallic Strip

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Chapter 4: Assignment: Baffle Your Skin (page 107)

Question: Is your skin a good instrument to determine how hot or cold an object is?

Hypothesis: (2 points) ___________________________________________________________

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Materials: Write in the space below (2 points)

Procedure: Refer to text, page 107.

NOTE: Make sure that you complete this with a parent or guardian. Ensure that the water is

not hot enough to burn your hands! Also, you may want to work on newspaper or around a

sink. Have towels ready to clean up.

Observations: (2 points)

In the space below, make some jot notes describing how your hands felt when you conducted the experiment.

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Analysis: 1. Describe how each hand felt in step two when you put both hands in the same bowl of water. Give possible explanations for your observations. (2 points) ____________________________________________________________________________________________________________________________________________________________

2. Was there any difference in your observations in step three to step two? If there was, suggest a possible reason why. (2 points) ____________________________________________ ____________________________________________________________________________________________________________________________________________________________

3. Use your observations to explain how the same air temperature can seem warm in the winter

and cool in the summer. (3 points)

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Conclusion: (What did you learn about your skin as a good instrument to determine the

temperature of an object?) (2 marks)

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Activity 4-1A Boiling Hot, Freezing Cold

In this activity you will try to match temperatures to descriptions of places or things. You will

probably be able to guess many of the temperatures of common things. Other temperatures

might surprise you. Using page 111 in your textbook, fill in the table below!

Very Cold Everyday Very Hot

1. Which temperatures surprised you the most? Why? _____________________________

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2. What was the most important thing that you learned from this exercise? ____________

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Key Terms

Body Temperature (p.112)

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Room Temperature (p. 112)

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Hypothermia (p.113)

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Thermometer (p. 122)

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Thermoscope (p. 122)

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Fahrenheit Scale (p.123)

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Celsius scale (p.124)

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Kelvin Scale (p.124)

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Calibrate (p.125)

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Bimetallic Strip (p.126)

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Thermocouple (p.127)

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Thermogram (p. 127)

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Comprehension questions

1. If you were asked what room temperature is, why would it not be possible to give a

specific temperature?

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2. What is hypothermia?

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3. Estimate the temperatures of the following items.

(a) a cup of soup __________ (b) the flame of a candle __________ (c) the record cold temperature in Québec __________ (d) an ice cream cone __________ (e) a person who has the flu __________ (f) a carton of ice cream in a freezer __________ (g) a container of juice in a refrigerator __________ (h) a container of juice on a kitchen table __________

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4. What is the difference between a thermoscope and a thermometer?

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5. Explain how Galileo’s air thermometer showed a change in the temperature.

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6. What does “absolute zero” mean?

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7. If you were told that an object had a temperature of –14°C, would you pick it up with

your bare hands? Why or why not?

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8. Explain why one person might touch an object and say it was cool while another person

touches the same object and says that it is warm?

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Comparison of the Kelvin (K), Celsius (ºC) and Fahrenheit (ºF) Scales

Place a ruler across each of the THREE thermometers to compare the following temperatures:

1. Boiling water = 373.15 Kelvin________Celcius ________ Fahrenheit

2. Water freezes = _______ Kelvin, ________Celcius ________Fahrenheit

3. Body Temperature _______ Kelvin, ______Celcius ________Fahrenheit

4. Room Temperature= ______ Kelvin, ______Celcius ______ Fahrenheit

5. Absolute zero = _______ Kelvin, ______Celcius ________ Fahrenheit

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Review of Key Terms

Create a list of 20 words or phrases from the descriptions below. Then find the words in the puzzle that follows. Words in phrases are not found together in the puzzle.

1. Can indicate whether you are sick

2. When the body is too cold to recover

3. Comfortable surroundings at home

4. Temperature measuring device in a thermostat

5. To put the correct scale on a thermometer

6. Sets zero for freezing point of water and one hundred for boiling point of water

7. First widely used temperature scale

8. Sets zero for coldest possible temperature

9. Temperature sensing device made of two metals in which electric current shows temperature difference between ends of metals

10. Image showing temperature that is taken with film sensitive to infrared radiation

11. Common temperature measuring device

12. Measures temperature changes but has no scale

13. If your body temperature is above 37 C, you might have this

14. These animals bask in the Sun to raise their body temperature

15. This scientist invented one of the first instruments for measuring temperature

16. Scientists often use this term to describe the coldest possible temperature

17. You can use this to set the temperature of your home

18. These are usually set at a temperature of 4 C

19. You might choose a temperature of 160 C if you are using this

20. To do this comfortably, many people set the temperature at 18 C

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E L B J G N F S Y T O T A E F

B R O I M A U G H A H A I T A

N A U O M I L E A E K R M U H

Y O O T S E R I R V E K R L R

D R I L A M T M L T P E E O E

O P E T O R O A E E J L H S N

B C E G C C E M L S O V T B H

H Z R E O E O P T L Q I O A E

H A E U L M F R M K I N P O I

M D P R R S I N J E M C Y V T

B L B E O P I N I C T M H E W

E W H T A T S O M R E H T N N

D T H T H E R M O S C O P E W

L I Z A R D S E L A C S E J A

R O T A R E G I R F E R K N S

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Chapter 4 Practice Test

Circle the letter of the best answer.

1. Which is normal body temperature for a person?

A. 37 C

B. 37 F

C. 98.6 C

D. 98.6 K

2. A temperature of 22 C would be normal for which case?

A. body temperature for a bird B. comfortable room temperature

C. outside temperature in Newfoundland and Labrador in January D. oven temperature when baking pizza

3. In what way does a thermoscope differ from a thermometer?

A. A thermometer has no scale. B. A thermoscope has a Fahrenheit scale and a thermometer has a Celsius scale.

C. A thermoscope has no scale. D. A thermoscope uses coloured water while a thermometer uses alcohol.

4. Which was the first widely used temperature scale?

A. Celsius scale B. Fahrenheit scale C. Kelvin scale

D. Thomson scale

5. What happens when a bimetallic strip is heated?

A. An electric current flows along the strip. B. Contracts because metals undergo thermal contraction. C. It bends because the two metals expand by a different amount.

D. Vibrates because the heating adds energy to the strip.

6. When you want to measure the temperature of an extremely hot gas, which is the best device to use? A. bimetallic strip.

B. glass thermometer. C. photographic film.

D. thermocouple.

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Match the term on the left with the best description on the right. Each description may be used only once.

Term Description

_____ 7. body temperature

_____ 8. room temperature

_____ 9. bimetallic strip

_____ 10. hypothermia _____ 11. thermogram

_____ 12. thermoscope

A. is used in thermostats to turn a furnace on and off

B. is a picture of infrared radiation given off by an

object

C. an electric current indicates temperature

D. causes the body to function so slowly that a

person might not recover

E. is higher for birds than for mammals

F. is an arbitrarily chosen temperature scale

G. is not a specific temperature but is a range of

temperatures

H. is the first temperature detecting instrument

developed by scientists

Short Answer Questions

13. Explain how to calibrate a thermometer. Use the pictures shown here to help with your explanation.

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14. What type of information can you get by taking your temperature? Give an example.

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15. Explain how at least three of your senses (sight, smell, and feel) can tell you that a

stove burner is hot.

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16. Describe what Fahrenheit used as 0 and as 100 when he selected values for his

temperature scale.

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17. Explain what causes a bimetallic strip to bend.

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18. Use the diagram below to explain how a thermostat turns an oven on and off.

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19. a) What is the name of this instrument? ________________________

b) Who invented it? __________________________

c) How can it be used to detect a temperature change ?

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