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Science 7Heat and
TemperatureStudent Notes Booklet
Name: ____________________Class: _________
SAFETY IN THE SCIENCE CLASSROOM
Name _______________________________ Class ___________ Date ____________
In science class, there will be times that experiments and investigations will occur. For the safety of all involved, it is very important to understand the basic safety rules that you will encounter in a science classroom. These rules are most important if any scientific research is done in the science labs or if you conduct your own science research. All these rules may not apply for your grade 7 school year, but it is important to know the facts for when you advance into other grades.
Instructions: Fill in the blanks using the following words:
Working With Your Teacher
Listen carefully to all _______________________________ given by your teacher.
________________________ your teacher of any medical conditions you may have that may prevent you from doing the lab.
Obtain your teacher’s ________________________________ before beginning any personal science experiment.
Know the location and the proper use of the nearest _________________________, _____________________________, first aid kit and ________________________.
After ClearDispose of Materials
Fire Extinguisher
Icons OneSafety Glasses
Ties
Approval Clothing Dry Gently Immediately Open Scarves Touch
Away Cord Dry Goggles Inform Pointed Sockets Trip
Broken or Cracked
Dangerous Equipment Gum Inform Plug Spills Tube
Carefully Dispose Face Hair Instructions Read Stools Understand
Carefully Drink Fire Alarm Hands Little Report Students Water
Carefully Directly Fire Blanket Heat Proof Long Necklaces Respect TasteWHMIS & Safety
Starting An Activity Or Investigation
________________________ and _____________________________ the investigation before starting an activity.
Carefully check the safety ______________________________ and understand all the safety precautions.
Begin an activity or investigation only _____________________________ your teacher tells you to begin.
Dressing For Success In Science
Wear protective ___________________________ and safety __________________ when using dangerous materials or when you are heating a substance.
Tie back long ______________________________.
Do not wear ___________________________, ____________________ or _____________________________.
Acting Responsibly
Make sure your work area is ________________________________.
Handle equipment and materials ________________________________.
Make sure that _________________________ and chairs are resting securely on the floor.
Report any ___________________________ activity to your teacher.
Handling Edible Substances
Do not chew ________________________, eat or _____________________ in your science classroom.
Do not __________________________ any substances or use your mouth to draw materials into a ________________________________.
Working In A Science Classroom
Familiarize yourself and understand all ___________________________ labels and symbols. (WHMIS)
Carry only _______________________ object or container at a time.
Make room for other _____________________________ who are carrying equipment to their lab station.
Working With Sharp Objects
Always cut ________________________ from yourself and others when using a knife or sharp razor blade.
Keep the _______________________________ end of the scissors facing away from yourself and others if you have to walk.
________________________________ any sharp or jagged edges on any equipment to your teacher.
___________________________ of broken glass in a designated area.
Working With Electrical Equipment
Make sure that your hands are _______________________ when touching electrical cords, plugs or __________________________________.
Pull the _______________________, not the ________________________ when unplugging electrical equipment.
Place electrical cords where people will not _________________________ over them.
Working With Heat
When heating something, wear ____________________________________.
Always use _______________________________ containers.
Do not use ______________________________ or _________________________ containers.
Point the ________________________ end of a container that is being heated away from yourself and others.
Do not allow a container to boil ____________________________.
Handle hot objects ____________________________.
If you receive a burn, apply cold _______________________________ to the burned area immediately.
Working With Various Chemicals
Wash area _________________________________ if your body comes into contact with a substance.
Do not ______________________________ your eyes, but wash immediately.
__________________________ your teacher of any accidents.
Never smell a substance _________________________________.
Hold containers away from your _______________________________ when pouring a liquid.
Working With Living Things
On a field trip, disturb the area as __________________________ as possible.
Move and remove items _______________________________ and ___________________________.
Treat all living things with _________________________________.
Cleaning Up In The Science Classroom
Clean up ______________________ according to your teacher’s instructions.
Clean ______________________________ before putting it away.
Wash your _________________________ thoroughly after doing an activity. Never __________________________ down a sink unless directed to do so.
I
want to see what you know about hot and cold temperatures. You can use your cell phones, ipods or a computer to help you with this task. MATCH the correct temperature (on the left) to the appropriate
description found on the right.
1. -273 C ____ Boiling temperature of water (at sea level)
H e a t a n d T e m p e r a t u r e
Boiling Hot, Freezing Cold
2. -218 C ____ Body temperature of a healthy human
3. -138 C ____ Hot chocolate or coffee
4. -89 C ____ Comfortable room temperature
5. -5 C ____ Soft ice cream
6. 0 C ____ Coldest temperature possible
7. 1 C ____ Melting point of aluminum
8. 7 C ____ Temperature of oven to bake cookies
9. 20 C ____ World record coldest air temperature
10. 37 C ____ World record hottest air temperature
11. 40 C ____ Air in a refrigerator
12. 58 C ____ Surface of the sun
13. 80 C ____ Lava from Hawaiian volcanoes
14. 92 C ____ Melting point of oxygen
15. 100 C ____ Ocean currents off Canada’s East coast
16. 180 C ____ Body temperature of a budgie bird
17. 357 C ____ Where the Space Shuttle flies in orbit
18. 660 C ____ Boiling point of mercury
19. 1150 C ____ Comfortable for heat-loving bacteria
20. 5550 C ____ A slush of pure water and ice
Topic 1 – Using Energy from heat
What is heat?
• _____________________________________ has been something scientists have been trying to figure out for years and years.
• Up until the 1600’s, people thought heat was a combination of fire an air.
• Hmmmmm…… interesting.
Finally! Scientists got it!
• ____________________ is a form of _______________________.
• The energy comes from the movement of tiny little ______________________________.
Humans using Thermal Energy
• What is thermal energy?
– The basic definition is __________________________________
Humans need heat in order to survive
• The four basic needs are:
– __________________________________
– __________________________________
– __________________________________
– __________________________________
• Heat is wrapped up in this….. Without heat (ESPECIALLY in CANADA)…. We build shelter to keep heat or cold away from us.
What is heat used for?
• Used for ______________________ and keeping _____________________________
Technology
• Through the advancement of _____________________________ we have been able to control the use of thermal energy
Changes in needs and wants
• The changes of our _________________________ and ____________________________ have advanced the uses of different thermal sources.
• From clothes drying on a line to electric dryers
• From hair drying ___________________________ to using a ___________________________ _
Making sustainable choices
• REMEMBER:
– _________________________________________ means that something that is being used is being replaced and the same rate.
– We need to use our resources wisely and do as little damage as possible to the environment when we use them
Time line
• Try to place the following items on the time line on the bottom of your note page:
– Central heating re-appears – using coal
– Humans create fire
– Electric Heaters
– Fireplaces with chimneys are built into the walls of buildings
– Cast iron stoves heat rooms evenly
– Romans develop central heating – heat travels from one source to different areas of a building
– Chimneys first appear in Europe
– Forced air heating
Lab Thermometers Scientific Inquiry
General Outcome 1: Students will Illustrate and explain how human needs have led to technologies for obtaining and controlling thermal energy and to increased use of energy resources
- Specific Outcome 1c : Students will identify and explain uses of devices and systems to generate, transfer, control or remove thermal energy
Performing and Recording: Students will Conduct investigations into the relationships between and among observations, and gather and record qualitative and quantitative data
- Students will use instruments effectively and accurately for collecting data and information
Problem:_____________________________________________________________________________________
19061800sLate 1700s1700s1300sA.D 1200100 B.C7000 B.C
__________________________________________________________________________________________________________________________________________________________________________
Hypothesis:____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Materials:
1. Lab thermometer2. Paper
Procedure:
1. With a partner, examine the thermometer carefully2. Notice where the glass is thick and thin3. Draw a full sized diagram of the thermometer in the center of your
observations section4. Put these labels on your diagram:
a. Liquid (colored ______________________________)b. Thick glassc. Bulb (storage space)d. Thin glasse. The scale (numbers)f. Freezing point of water (_______________)g. Boiling point of water (______________)h. Average room temperature (_______________)i. Average normal body temperature (____________)
5. Place your hands around the middle of the thermometer, record your observations
6. Place your hands around the bulb, record your observations.
Observations:
A. Draw your LABELLED thermometer here (labels come from #4 in the procedure)
B. Place your hand around the middle of the thermometer Record your observations here
C. Place your hand around the bulb Record your observations here
Analysis:
1. The bulb is an important part of a liquid thermometer. Give reasons why.
2. Which part of the thermometer has the thinnest glass? Why do you think it is made like this?
3. How many Celsius degrees are there between the freezing point of water and the boiling point of water?
4. Find out why mercury is no longer used in making thermometers for use in school.
Conclusion:
Errors and Changes:
Measuring Temperature – Topic 2 Part 1
Temperature
• In general, what do you think temperature measures?
_______________________________________________________________________________________________________________________________________________________________________________________
Do you know?
• What are the two most common ways to measure temperature?
1. ____________________________________________2. ____________________________________________
Examples:
• Sight Glowing metal
– Does red mean hot? What other colors mean hot?
• Touch A forehead with a fever
Question
• Are your senses always reliable????
____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Thermometers
• Look at the _____________ thermometer and the ______________________ thermometer….. What is missing from these thermometers that we now have today?
The missing piece
• The main piece missing from the thermometers was a _________________________________.
• A scale is markings of _______________________ to indicate a precise temperature.
Tell me…
• Do you know who ____________________________ was? What do you think he contributed to the ideas of temperature?
• Canada uses the _______________ scale. He used the ___________ as a unit of temperature.
• Anders Celsius assigned:
• ______________ to the temperature where ___________________ at sea level
• _______________ to the temperature where ___________________ at sea level
Question 2
• What is meant by _________________________? What two fixed temperatures in Celsius are used for calibration?
Calibration
- _____________________ means to set the starting point
Steps to Calibration
• ______________________:
– Mark on the thermometer where 0oC is by putting the thermometer in an ice bath
• ______________________:
– Mark on the thermometer where 100oC is by putting the thermometer in boiling water
• ______________________:
– Divide the scale into 100 equal parts between 0oC and 100oC
Not always accurate
• Using Celsius’ scale is good, but not always _______________________________.
– Can you think of some reasons why???
• 1. ____________________________________
– Because Alberta has high pressure (much higher than sea level), water boils below 100oC
• 2. ________________________________________
Textbook time
• Read page 194-195 ( in science focus 7) and answer these questions:
– After the creation of the Celsius scale, what new scale was developed?
– Why did we need this new temperature scale?
Topic 2 Part 2 – Devices for measuring temperature
The Kelvin Scale
After the creation of the Celsius scale, the ________________________ was created because new gases were being discovered.
Scientists required a more accurate reading of high and low temperatures.
Absolute Zero
____________________________ is the coldest possible temperature
◦ Absolute zero on the Celsius scale is ____________________________________
◦ Absolute zero on the Kelvin scale is _____________________________
What is the difference between heat and temperature?
_________________________________ is a measure of energy of the particles moving around
◦ _________________________________________ is HEAT!
________________________________________ is a measure of how hot or cold something is measured on a scale like a thermometer.
How does a thermometer work?
Explain in general how a thermometer works using the terms __________________________, _____________________________ and ______________________.
◦ Page 199
__________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Thermocouple
Description
◦ - wires of two different metals are twisted together (copper and iron)
◦ - when heated it produces an _____________________________________
Use
◦ - turn switch on or off it temperature changes
Reason for Development
◦ - measures high temperatures
◦ - cannot be used to measure _________________________________________
Bimetallic Strip
Description
◦ - two metals fused together
◦ - expands at different rates
◦ - coils when heated - reverses when cools
Use
◦ - operates electrical switches
◦ - controls furnace (_______________________________), air conditioner, fridge
Reason for Development
◦ - easy way to turn something on and off automatically
Recording Thermometer
Description
◦ - a ________________________________________ joined to a lever with a pen
Use
◦ - records small movement of temperature change
◦ - weather records
Reason for Development
◦ - records temperature over a period of a week
Infrared Thermogram
Description
◦ electronic sensor or device that photographs temperature change through _____________________________________
◦ photographs _________________________________________________
Use
◦ detects air leaks
◦ energy efficient
◦ can be used to predict dangers of over heating
Reason for Development
◦ detects precise temperature change - not visible to the eye
◦ quick and accurate
To measure temperature
1. Thermometer
2. Thermocouple
3. Bimetallic Strip
4. Recording Thermometer
5. Infrared Thermogram
Thinking Time!
Which tool for measuring and controlling temperature would be most affective?
1. Controlling an electric frying pan?______________________________________________________________________________
2. Making long term records at the weather office?______________________________________________________________________________
3. Detecting small forest fires before they spread? ______________________________________________________________________________
Topic 3 Part 1 – the Particle Model of Matter and States of Matter
Question:
• What scientific explanation is given to explain why moving your hand through the air is easier than moving your hand through water, wood or steel? _________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
States of Matter
• There are three “states” matter can appear in.
– 1. ___________________________________
– 2. ___________________________________
– 3. ___________________________________
Question:
• Name the states(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 _______________________________
The Particle Model of Matter
• Liquids can turn into gases or solids
• Gases can turn into liquids
• Solids can turn into liquids
• HOW DO WE EXPLAIN THIS?!?!?!?!
– We use the
__________________________________________________________
• 1. All matter is made up of extremely tiny particles.
• 2. The tiny particles of matter are always moving
• 3. Adding heat to matter makes the particles move around faster
• 4. The particles have spaces between them.
• How does the particle model of matter connect with state changes (solids, liquids and gases)?
____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Kinetic Energy
• When particles or any object is moving, we say it has ____________________________.
– Kinetic energy is the energy of movement.
– Particles in a solid have a ________________ kinetic energy but particles in a gas have ________________________ kinetic energy.
Particles in a Solid State
• The particles are so close together that a solid has a definite _______________________ and _________________________________
• ___________________________________ is the amount of space that matter occupies.
Particles in a liquid state
• Particles in a liquid are loosely _________________________________ to each other
• Liquids will take the shape of its _________________________________ and has a definite volume
Particles in a gas state
• The particles are ________________________________ connected to one another.
• Gas will _____________________________________ in a container but has NO set shape.
What happens if we heat it up?
• Let’s do a little experiment and see if you can explain what is happening.
• We are going to use cold water and hot water. We will add food coloring to each of the temperatures of water and observe what happens.
____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
CSI: CRIME SCENE INVESTIGATION
Calgary, Alberta, a city who has a reputation for being quite beautiful
and full of all sorts of unique attractions has brought an influx of visitors to the southern
Alberta city. From the Calgary Flames, to the Calgary Zoo, Calgary has long been a place for visitors. BUT, these attractions have made the city a ripe target for criminals of all varieties, confident they will never be caught. Unfortunately for them, most are proven wrong by the Calgary Police Services’ night shift Crime Scene Investigations unit led by none other than our grade 7 science classes.
With almost obsessive dedication towards their quest for the facts, the team with their elite investigators works various cases using scientific skills and equipment that are capable of finding valuable clues from the most seemingly unlikely sources. In a city of empty dreams, as the Flames have yet to win a Stanley Cup in many years, the grade 7 science classes lead the quest for the one thing that can cut through the lies to the truth and justice, the evidence. DUN, DUN, DUN!!!!! Frosty has disappeared and the CSI team is needed to figure out his whereabouts. Read the facts below to try and crack the case.
The FACTS:Frost was last seen by a group of children who were out having some winter fun in the snow. Frosty the snowman seemed in quite a hurry that one day, suspiciously looking to the sky. He seemed nervous. But he waved goodbye saying, Don’t you cry, I’ll be back again someday.”
It appears as though there was some foul play involved. He has not been seen in quite some time. It appears as though he has disappeared for good. He was last seen December 20, 2015 at 7:23 am. The weather on December 20, 2015 at 7:23 was 3oC and the average temperature of the past week has been 4.3oC.
Crime Scene Investigators, we NEED you! Look at the facts and try to provide an explanation to what may have happened to Frosty. Please be sure to look at the check list to be sure you have explained everything required when doing up your report. You may use pictures, paragraphs, explanations or combinations of all of these in order to crack the case.
Death of Frosty Medical Examiner Report Checklist
General Outcome 2: Students will Describe the nature of thermal energy and its
Frosty has Disappeared
effects on different forms of matter, using informal observations, experimental evidence and models
- Specific outcome 2b: Students will describe the effect of heat on the motion of particles; and explain changes of state, using the particle model of matter
- Specific Outcome 2c : Students will distinguish between heat and temperature; and explain temperature, using the concept of kinetic energy and the particle model of matter
Three states of Matter referred to and explained:
Solid Liquid Gas
Each state is defined in terms of:
Spaces between particles Bonds between particles Movement of particles (Kinetic Energy)
Transitions between states of matter refers to:
Heat Energy
Mention of:
Heat Temperature
Comments by Medical Examiner:
Have a friend go over your investigation as well as your teacher. Have both a friend and your teacher make comments on your investigation providing at least one area for improvement and one area of excellence.
Friends comments:
Teachers comments:
Particle Model of Matter and States of Matter Review
A. Write the four steps of the particle model of matter1.
2.
3.
4.
B. Using a chart, describe and explain the three states of matter (Solid, Liquid and Gas) and what happens between each of these states (Freezing, Melting, etc.)
C. Explain how an ice cube that is taken out of a freezer changes as it turns into a gas. You may use diagrams or descriptions or both.
D. Explain what each of the following LOOKS like in terms of their particles and the spaces between them
Solid
Liquid
Gas
E. Create a cartoon strip with captions that illustrates the changes in particles from a solid state to a gas.
Topic 4 – Expansion and Contraction
Heatin’ Up
• If materials are warmed up, the particle model of matter says:
– 1. particles ___________________________________
– 2. particles ___________________________________
• THE MATERIAL EXPANDS
• _______________________ is an increase in volume. The particles move faster and spread apart.
Examples
• How does a bimetallic strip bend? Remember it is made of TWO different types of metal. __________________________________________________________________________________________________________________________________________________________________________
- Ball and ring o How can we make it so the ball DOES not fit through the ring?
Make the particles move faster and farther apart so they expand in the ball
- Trains o Trains make the “Clickety-Clack” sound.
What are these “teeth” meant to do?____________________________________________________________________________________________________________________________________________________________
- Power lines sag in the summer time. Why don’t we tighten them up?____________________________________________________________________________________________________________________________________________________________
Contraction
• __________________________ is when a substance decreases volume as they cool down.
• What happens to the particles in a substance as they contract?
– The particles slow down and move closer together.
Expansion and contraction in gases
• ___________________ can expand and contract much more than __________________….
Find out Activity – Page 211
Carefully read all of the information on the Find Out Activity on Page 211
1. Examine Table 1 and use it to answer the following questions.
• A) What similarity do you see in how all the materials react as they warm?
• B) In what ways do the materials react differently as they warm?
• C) which material expands the most as it warms?
• D) Which material expands the least as it warms?
2. Copy the list of materials in Table 1, but arrange them in order, starting with the material that expands the most and end with the one that expands the least.
Important Information
• Only the _______________________ of the objects are affected when a substance is expanding and contracting, _______________________________________
• The size of the particles does not change; only the amount of space between them
Topic 5 – Particle Model and Changes of State
The beach….. Ahhhh….
• On a hot summer day does the sand on the beach warm slowly or quickly?
• ____________________________________________
• Does a LARGE body of water warm slowly or quickly?
• _____________________________________________
The water and the sand have different ____________________________________.
• What do you think this means?
__________________________________________________________________________________________________________________________________________________________________________
Heat Capacity
• __________________________ is the amount of thermal energy that warms or cools an object by one degree Celsius.
• _____________________________ is the amount of thermal energy that warms or cools _____________________________ of a material by one degree Celsius.
High and low heat capacity
Does sand have a HIGH or LOW heat capacity?
_____________________________________________________________________________________
Does water have a HIGH or LOW heat capacity?
_____________________________________________________________________________________
Your Turn Explain if each item has a high or low heat capacity
Material Warms Quickly or Slowly?
Heat Capacity Low or High?
The bottom of a cooking potA cold pack for treating athletic injuriesSolid glue in a glue gun
Changes of State
• Using a ruler and a pencil carefully draw and label Figure 3.18 - Changes of State found on page 220 (Science focus 7).
Changes of State Change Releases or Requires Energy?
Melting (Fusion)
Freezing (Solidification)
Evaporation
Condensation
Sublimation
Examples Read each statement. Then write a description of each statement using a “science-y” word
1. Wet Clothes dry in the sunshinea. Description: Evaporation of liquid water
2. Melted wax in a candle hardens when the candle is blown outa. ______________________________________________________
3. A warm wind makes snow on the ground disappear, but no puddles of water form.
a. ______________________________________________________4. In the winter, invisible moisture in the air sometimes forms frost on car
windshields.a. ______________________________________________________
Assignment Carefully read page 221 – “What Happens when a Liquid Evaporates?”
In your own words, explain the phenomenon called ______________________________
Question of the day
• Anyone who falls into a lake fully clothed may develop hypothermia after being rescued. No matter whether the water and the weather are warm or cold, first-aid experts say that the victim’s wet clothing should be removed immediately. Use your knowledge of energy and change of state to explain why.
Topic 6 – Transferring Energy
Let’s see what you remember…
• Describe what happens to the volume of solids, liquids and gases as they warm and cool.
___________________________________________________________________________________________________________________________________________________________________________
• Use the particle model of matter to describe, in detail, what happens to water in a fishbowl that is located in a sunny window. (Keep volume and evaporative cooling in mind).
__________________________________________________________________________________________________________________________________________________________________________
Vocabulary for Topic 6
• _____________________________________________
– the transfer of energy in the form of electromagnetic waves
• _____________________________________________
– energy that is transferred in the form of electromagnetic waves
• _____________________________________________
– the direct transfer of thermal energy from one particle or object to another through contact and collision
• _____________________________________________
– materials that slow the transfer of conduction of thermal energy from one object to another
• _____________________________________________
– materials that increase the efficiency of heat conduction or the transfer of thermal energy form one object to another
• _____________________________________________
– materials (liquids or gases) that lack a definite shape and can flow from one place to another
• _____________________________________________
– a process by which a warm fluid moves from place to place carrying thermal energy
• ______________________________________________
– continuous circulation of a fluid (either a liquid or gas), in which thermal energy is transferred from hotter, less dense fluid to colder, more dense fluid
Unit Three: Heat and TemperatureTopic 6: Transferring EnergyReading Assignment (pages 226 – 236)
General Outcome 2: Describe the nature of thermal energy and its effects on different forms of matter, using informal observations, experimental evidence and models
• compare heat transmission in different materials (SO A)
General Outcome 3: Apply an understanding of heat and temperature in interpreting natural phenomena and technological devices
• compare and evaluate materials and designs that maximize or minimize heat energy transfer (SO C)
• describe and interpret the function of household devices and systems for generating, transferring, controlling or removing thermal energy (SO E)
Three ways that energy can be transferred are:
1. Radiation2. Conduction3. Convection
Radiation- transfer of energy without any movement of matter (radiant energy or electromagnetic
radiation – EMR)- radiant energy travels like a wave (ripple action)- can travel through empty space, air, glass and other materials- examples include radio waves, microwaves, visible light, x-rays and the sun’s energy (heat
radiation)
Common Characteristics of Radiant Energy- behave like waves- can be absorbed or reflected- travel across space at a very high speed (300 000 km/s)Thermal energy is transferred from the heat source in the form of a wave. The wave can travel through materials, and even through empty space. The radiant energy is absorbed or reflected by objects in the path of the wave.
Check Your Understanding of Radiation
1. When you sit in front of a fire, you feel warmed by radiant energy. When someone stands between you and the fire, you feel cold again. Explain why this happens. Draw and label a diagram to illustrate your explanation.________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
2. Why are white or light-coloured clothes recommended for hot, sunny locations?
________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
3. Why did the Apollo astronauts wear shiny suits on the moon?
________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
4. Explain how insulation between the outer and inner walls of a home helps to reduce thermal energy transfer.
________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
5. Explain how a reflective film on windows helps to keep a home cool in the summer but warm in the winter.
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
Conduction
- the transferring of thermal energy from one particle to another (collision/colliding of particles)- conduction occurs in solids- particles in liquids and gases are too far apart for conduction to take place- some solids are excellent conductors (gold, copper) because they allow the transfer of
energy- some solids are poor conductors (glass, wood) because they prevent the transfer of energy
– these are called insulators- R-Value is a measurement used on insulators to know the degree to which it is an effective
insulator – the higher the value the better the insulator
Particles near the heat source absorb energy from it. They begin to vibrate more rapidly.
The fast-moving particles bump into neighbouring particles, increasing their energy and motion.
Neighbouring particles bump into their neighbours, and so on. In this way, thermal energy is transferred throughout the material.
1. On a cold winter day, why would an iron post in a park feel much colder to the touch than a wooden bench?
2. Potatoes cook from the outside in.(a) Why does a small potato cook faster than a large potato?
(b) Why does sticking a metal skewer through the middle of a potato make it cook faster?
3. A metal spoon is used to stir a pot of hot soup. Draw three diagrams to show the behaviour of the particles in the spoon. Write captions to help explain what each diagram illustrates.
Convection
- a continuous cycle of warm fluid or particles rising from a heat source, cooling and sinking back down toward the heat source ( the process repeats)
- examples of the use of this process is seen in a furnace, boiler, stove and dryer
Check Your Understanding of Conduction
Particles near the heat source absorb energy and become warmed. The less dense, warmed column of particles pushes up through the fluid. The surrounding cooler particles sink and move in to replace the rising column of warm particles
1. Sea and land breezes are convection currents that occur in nature. Warmer air rises and cooler air moves in to take its place.
(a) During the day, the land heats up faster than the sea. The warmer air above the ________rises. This allows the __________ sea air to move in, causing a sea breeze. In the space below, draw and label a diagram of the air currents during a hot, sunny day by the sea.
(b) During the night, the land cools faster than the sea. The warmer air above the __________ rises. The cooler air over the __________ moves in to take its place, creating a land breeze. In the space below, draw and label a diagram of the air currents during a night by the sea.
(c) Under what conditions would no breezes occur?
Insulators and ConductorsLearning Outcomes:
compare heat transmissions in different materials (GO 2A) explain how heat is transmitted by conduction, convection and
radiation in solids, liquids and gases (GO 2B) compare and evaluate materials and designs that maximize
or minimize heat energy transfer (GO 3C)
Key Notes: Conductors
Check Your Understanding of Convection
- materials that allow easy transfer of heat energy- most metals are good conductors of thermal energy such as copper,
iron and goldInsulators
- materials that do not allow for easy transfer of heat energy- examples include plastic, cork and wood
Insulators are often used in construction to keep homes warm in the winter and cool in the summer.*************************************************************************R-ValuesSome materials do a better job at insulating than others. Materials are given an R-value or RSI value. The R-values tell the consumer how well the material will insulate or rather keep heat from transferring to another material.
The higher the R-value, the better the product is at providing insulation.
RSI (Relative Strength Index) of Various MaterialsMaterial RSI per cm of ThicknessBlue Plastic Foam Panels 0.35White Plastic Foam Panels 0.29Fiberglass 0.24Vermiculite 0.16Plywood 0.087Glass 0.017Brick 0.014Aluminum 0.000 05Still Air 0.15Newsprint 0.28
Heat Insulators WorksheetInsulators are important for energy efficiency – it stops heat from leaking out of your home and into the environment. Insulators help to keep down the cost of both natural gas and electrical use in your home.Calculation Example:Extra thickness increases the RSI value because it is based upon 1 cm of material.
Example: 3 cm of fiberglass3 X 0.24 =
1. Calculate the RSI value of a 12 cm thick brick wall.
2. Calculate the RSI value of a wall made of 2.5 cm of plywood and 1 cm of still air.
3. Calculate the RSI value of a wall made of 5 cm of aluminum, 10 cm of brick and 20 cm of fiberglass.
4. Calculate the RSI value of a wall made of 1.3 cm blue plastic foam panels, 0.6 cm of aluminum and 5 cm of brick.
5. Calculate the RSI at the bottom of a tent lined with 3 cm of newsprint.
6. Rank the materials in order of best insulating ability to worst insulating ability.
7. Compare (quantitatively) the RSI value of a triple-glazed window (3 panes of glass each 0.3 cm thick and two air spaces each 1.0 cm thick) with a double glazed window (the same particulars).
Radiation – How Can We Use It?
The Difference between Passive and Active Solar Energy
Learning Outcomes: compare heat transmissions in different materials (GO 2A) explain how heat is transmitted by conduction, convection and radiation in solids, liquids and gases
(GO 2B) describe ways in which thermal energy is produced naturally (GO 3A) describe examples of passive and active solar heating and explain the principles that underlie them
(GO 3B) compare and evaluate materials and designs that maximize or minimize heat energy transfer (GO
3C)
Passive Solar EnergyKey Ideas:
A passive system is heated directly by the sun’s rays. It is designed to heat a building without fans or pumps to carry heat to different parts of the
building.
The basic approach for passive solar heating is simple – reduce heat loss and increase heat gain from the sun.How to Use Passive Solar Energy in Your Home:
1. Insulate the building as much as possible – especially in the places with the greatest heat loss – windows, doors, walls, floor, ceiling and roof.
2. Place large windows on the south side of the building.3. Place small windows on the north side of the building.4. Plant deciduous trees on south side of the building and coniferous trees on the north side of the
building.5. Build a large overhang over the window to keep out the summer sun and let the in the winter sun.6. Have a stone or brick wall in the direct path of the sunlight so that it will give off heat when the sun
goes down at night.
Using the outline of the house and the information from above show your understanding of how passive solar heating can be used to heat this structure.
N
Active Solar EnergyKey Ideas:
Heating that requires a mechanical device to carry heat to other parts of the building. Radiation brings energy to the home, but convection makes the heat energy move throughout the
house with the use of a device.Active Solar Heating Systems Have 3 Main Parts:
1. Energy Storage Collector2. Storage Unit3. Distribution System to Spread the
Heat
Using the outline of the house and the information from above show your understanding of how active solar heating can be used to heat this structure. (Label the Diagram)
Refer to Page 226 in Science in Action.
When using a passive solar heating system in Alberta, there must be a back-up system to provide the structure with heat in case there is not enough sun received – especially in the winter!
Where Does the Most Heat Loss Occur In a Home?(Refer to Page 234 SIA)
Topic 7 – Sources of Thermal Energy
Key Vocabulary• _______________________________________________
– an object or material that can transfer energy to other objects
• _______________________________________________
– solid, liquid or gas hydrocarbons formed from parts of plants and animals over millions of years
• _______________________________________________
– resources that take millions of years to form
– not renewable
– once they are gone, they are gone
• _______________________________________________
– energy resources that can be recycled or replaced by natural processes in less than 100 years
• ________________________________________________
– a warming of the environment that results from human activities, such as burning of fossil fuels
Types of Thermal Energy• _______________________________________________
– the energy stored in food and fuels
– heat is released from food and fuels through a chemical process of burning
– Food is digested releasing energy
– fuels, such as wood, coal and other fossil fuels burn to release energy
• _______________________________________________
– energy stored in moving water can be used to generate electricity (hydroelectricity)
– produced at generating stations that burns fuels to produce electricity
– electricity is sent to homes and industries through a system of wires
– this type of energy production has caused negative effects on the environment
Ways Electricity is Created- ____________________________________________________________
o Using the power of falling water to produce electricity - ____________________________________________________________
o Burning coal and natural gas for energy
Mechanical Forces• _______________________________________
– thermal energy produced by the force of friction (the rubbing of two objects)
– mechanical forces that push and pull objects release thermal energy (car brakes, bicycle brakes, skidding tires)
Geothermal Energy• ________________________________________
– energy that is harnessed from the Earth’s interior
– examples include erupting volcanoes, geysers and hot springs
– good, clean and reliable energy source
Solar Power• _________________________________________
– energy from the Sun
– clean and a resource that will always be available, however inventions are continually being created to harness this great power
Wind Power• __________________________________________
– energy of moving air
– created by convection currents
– windmill invention has been used to capture the power of the wind to generate electricity
Nuclear Power• _____________________________________________
– a process that uses small amounts of radioactive uranium to produce vast amounts of heat
– non-renewable
– nuclear power plants produce large quantities of electricity
– requires special handling
– major problem is the long term storage of nuclear waste
Topic 7: Energy ConsumptionGive it a Try:
• Make a list of your everyday activities that require energy.
• How could we reduce our energy consumption?
:
• Reduce energy consumption by…
• Energy Efficient Lighting
• Devices that control power consumption of appliances
• Low flow shower heads
:
• Approximately 50% of the oil used in Canada is used by cars and trucks
• Which uses a lot of energy and causes pollution
:
• Walking, biking, public transportation, car pool
• Combine outings into one efficient trip
• Drive fuel efficient vehicles
•
:
• Is the biggest energy user
– They have offices and factories that need to be lit
– Multiple computers, photocopies, and other office machines
– Factories use energy to produce products
• to reduce energy consumption
– Identify energy inefficiencies and ways to become more efficient
:
– a method of energy conservation by which waste heat or energy from one industry is used by another industry
Unit 3 Review
Heat and Temperature
Topic 1:
Using Energy from Heat
What is Thermal Energy?
- the basic definition is heat- used for cooking and keeping warm- through the advancement of technology we have been able to control the use of thermal energy- changes in needs and wants have advanced the uses of different thermal sources
Examples: clothesline drying to drying machine
Topic 2: Measuring Temperature
Temperature- defined as how hot or cold something is (this is the basic definitions BUT you must also know the scientific
definition)- may be estimated by touch and sight
Thermometers
- first thermometer invented by Galileo- he invented the air thermometer on the basis that air expands when heated- liquid use was then developed on the same premise- mercury was used – did not stick to glass tubing and had appropriate freezing and boiling points- alcohol thermometer most commonly used
Steps in Calibrating Thermometers- in order for a thermometer to be accurate it must be calibrated
3 Steps: 1) freezing temperature (ice water)
2) boiling temperature
3) equal divisions marked between 2
points
Temperature ScalesTypes: 1) Celsius Scale
2) Kelvin Scale
3) Fahrenheit Scale
** Review fixed temperatures and well known temperatures on all three scales – boiling point, freezing point, body temperature, room temperature, absolute zero.
Thermometers- different types of thermometers for different purposes- each thermometer contains a sensor, signal and a responder
Types of Thermometers1) Thermocouple
2) Bimetallic Strip3) Recording Thermometer4) Infrared Thermogram
** Refer to your notes and review over their uses and development.
Topic 3:
The Particle Model, Temperature and Thermal Energy
The Particle Model (How Particles Behave in a Substance)4 main points
- all substances are made up of tiny particles too small to be seen- constant motion- spaces between particles- motion of particles increases/decreases when the temperature increases/decreases
** Really understand the last point to the particle model of matter as you need to relate this point to the scientific definition of temperature and thermal energy
Three States of Matter- solid, liquid and gas - behaviour of particles act differently in each state (movement, shape and volume)- refer to your reading assignment about how these particles behave in each of their states
Thermal Energy (Heat)- energy that flows to or from a substance- transferred from hot to cold- total kinetic energy- the faster the particle motion the higher the thermal energy- measured in Joules
Temperature- particle motion and temperature are directly related- increase in temperature increases particle motion and vice versa- the average speed (average kinetic energy) of particles in motion- measured in degrees Celsius
** Look back and review over the tea cup and pail example – Eureka video – the difference between thermal energy and temperature… why is there a difference…
Energy- something’s ability to do work or to cause change (example: charged battery)- energy is transferred or transformed from one energy type to another (electricity to light)- does not have mass- cannot be created or destroyed- it is a state, quality or a condition- energy transfers in one direction (high to low OR hot to cold)- Law of Conservation of Energy
Topic 4: Expansion and Contraction
Expansion- as thermal energy is added the particles move faster and spread apart, causing an increase in volume
Contraction- as thermal energy is removed the particles slow down and move closer together, causing a decrease in volume
Expansion and Contraction of Solids- all solids expand and contract at different rates when heated and cooled- each solid has a unique characteristic (eg. copper, steel and concrete)- solids expand very slowly as compared to liquids and gases due to the strong bonds between the particles- the small change adds up in relation to large structures therefore expansion and contraction rates of materials must be
considered in construction- refer to lab examples – bimetallic strip and ball and ringExpansion and Contraction of Gases- particles in gases are farther apart than those in solids and the forces of attraction are much weaker- any increase in temperature will causes the gas particles to move rapidly away from each other, so gases expand more
than solids given the same temperature change- refer to lab examples – balloon and flaskExpansion and Contraction of Liquids- all liquids expand and contract at different rate (eg. mercury, alcohol, oil, water, vinegar)- refer to lab example – heart meter
**Think of everyday examples of expansion and contraction – railroads, bridges, buildings, expansion joints, sidewalks, bowl of soup, hot air balloons, telephone wires… etc.
Topic 5: The Particle Model and Changes of State
Heat Capacity- the amount of thermal energy that warms or cools an object by one degree Celsius
Types:
a) Low Heat Capacity – objects that warm and cool quickly (sand example)b) High Heat Capacity – objects that warm and cool slowly (water example)
Changes of State
The six changes of state include:1) solidification – liquid to solid2) fusion – solid to liquid3) condensation – gas to liquid4) evaporation – liquid to gas5) sublimation – solid to gas6) sublimation – gas to solid
- any pure substance can exist in all three states of matter- during a phase change the temperature stays constant (hidden or latent heat)- particles become less organized as their energy increases (solid-liquid-gas)- particles become more organized as their energy decreases (gas-liquid-solid)** Refer to diagram/graph in notes to explain what happens to the organization of particles as their energy increases/decreases.
Evaporative Cooling- the phenomenon that as particles evaporate they become cooler- fast moving particles (warm) escape leaving behind slow moving particles (cool)- any surface it comes in contact with cools as well (example: perspiring)
Topic 6: Transferring EnergyThree ways that energy can be transferred are:
4. Radiation5. Conduction6. Convection
Radiation- transfer of energy without any movement of matter (radiant energy or electromagnetic radiation – EMR)
- radiant energy travels like a wave (ripple action)- can travel through empty space, air, glass and other materials- examples include radio waves, microwaves, visible light, x-rays and the sun’s energy (heat radiation)
Common Characteristics of Radiant Energy- behave like waves- can be absorbed or reflected- travel across space at a very high speed (300 000 km/s)Conduction
- the transferring of thermal energy from one particle to another (collision/colliding of particles)- conduction occurs in solids- particles in liquids and gases are too far apart for conduction to take place- some solids are excellent conductors (gold, copper) because they allow the transfer of energy- some solids are poor conductors (glass, wood) because they prevent the transfer of energy – these are
called insulators- R-Value is a measurement used on insulators to know the degree to which it is an effective insulator – the
higher the value the better the insulatorConvection
- a continuous cycle of warm fluid or particles rising from a heat source, cooling and sinking back down toward the heat source ( the process repeats)
- examples of the use of this process is seen in a furnace, boiler, stove and dryer
Features of Energy Transfer Systems1. Energy Source2. Direction of Energy Transfer3. Transformations4. Waster Heat5. Control Systems** Refer to your reading assignment for an explanation of each of the following features of energy transfer systems. There are also examples in your reading assignment.
Types of Thermal Energy
1) Chemical Energy - the energy stored in food and fuels- heat is released from food and fuels through a chemical process of burning- food is digested releasing energy- fuels, such as wood, coal and other fossil fuels burn to release energy2) Electrical Energy - energy stored in moving water can be used to generate electricity (hydroelectricity)- produced at generating stations that burns fuels to produce electricity- electricity is sent to homes and industries through a system of wires- this type of energy production has caused negative effects on the environment3) Mechanical Forces - thermal energy produced by the force of friction (the rubbing of two objects)- mechanical forces that push and pull objects release thermal energy (car brakes, bicycle brakes, skidding
tires)4) Geothermal Energy - energy that is harnessed from the Earth’s interior- examples include erupting volcanoes, geysers and hot springs- good, clean and reliable energy source5) Solar Energy - energy from the Sun- clean and a resource that will always be available, however inventions are continually being created to
harness this great power
6) Wind Energy - energy of moving air- created by convection currents- windmill invention has been used to capture the power of the wind to generate electricity
Define:
1. energy resource2. fossil fuels3. non-renewable resources4. renewable resources5. thermal pollution6. cogenerationTopic 8: Conserving Our Fossil Fuel Resources- fossil fuels are important part of our economy, but the burning of them has created so many disadvantages- we believed that this resource was readily available and that the environmental effects were minimal- this idea has changed as scientists have done more research
Danger: Thermal Energy- harmful effects obvious (forest fires, pollution)- industries responsible for containing and storing dangerous chemicals and products
By-Products of Thermal Energy Use
1) Carbon Dioxide
- burning of fossil fuels (cause of global warming)
2) Sulfur Dioxide- irritant to eyes, nose and throat- companies and industries put a lot of money into research to reduce these emissions
3) Carbon Monoxide
- lethal gas – poisons brain – inability to reason and function
Knowledge of the dangers of thermal energy will help you make proper environmental choices.
Questions:1. What is the basic definition of thermal energy?2. What are the two main uses of thermal energy?3. What are the two ways that temperature may be
estimated?4. Who invented the first thermometer?5. What was the name of Galileo’s first
thermometer?6. What are the two most common liquids used in
laboratory thermometers?7. How may the accuracy of the Celsius scale be
affected?8. What are the three steps in calibrating a
thermometer?9. Name three temperature scales.10. What scale is used for scientific measurements?11. What is the freezing point of water on the
Celsius scale?12. What is the boiling point of water on the Celsius
scale?13. What is absolute zero?14. What is absolute zero in degrees Celsius? Kelvin?15. What are the three main parts of every
thermometer?16. What thermometer produces an electrical
current?17. This measuring device is used to turn on and off
an electrical switch.18. Used to measure temperature over a long period
of time.19. This thermometer uses infrared radiation and
color to indicate temperature.20. What is body temperature in the Fahrenheit
scale?21. What are the four main points of the particle
model of matter?22. Thermal energy is measured in this standard
unit.23. What direction does energy flow?24. What is the scientific definition of temperature?25. What is energy?26. What is expansion?27. What is contraction?28. What are the key characteristics of an object
with low heat capacity?29. What are the key characteristics of an object
with high heat capacity?30. What is solidification?
31. What is fusion?32. What is condensation?33. Name the change of state from liquid to gas.34. Name the change of state that bypasses the
liquid state.35. What happens to the temperature of a
substance during a phase change?36. What is the name of the phenomenon in which
particle cool as they evaporate?37. What is latent heat or hidden heat?38. What does EMR stand for? What are the three ways that energy may be transferred?
39. What are the three characteristics that all types of radiant energy share?
40. Name two examples of radiant energy.41. Of what state of matter does conduction occur?42. What is the special name given to those
materials that are not good conductors?43. What solid types are the best conductors?44. What is convection?45. Where or how are convection currents used?
46. List 5 features that all energy transfers have in common.
47. What is chemical energy?48. What type of electricity is produced by moving
water?49. What is an example of mechanical forces?50. What is geothermal energy?51. What is solar energy?52. What is nuclear energy?53. What is active solar energy?54. What is passive solar energy?55. How can wind energy be harnessed?56. What is a non-renewable resource?57. What is a renewable resource?58. What are greenhouse gases?59. What is cogeneration?60. What is thermal pollution?61. What are three negative by-products of thermal
energy?62. What is matter?63. Does energy have mass?64. What state of matter fills the container in which
is was placed?65. What state of matter has a definite size, but no
fixed shape?66. What is a pure substance?ANSWERS1. Answer: heat2. Answer: cooking and heating3. Answer: touch and sight4. Answer: Galileo5. Answer: air thermometer6. Answer: alcohol and mercury7. Answer: pressure, sea level and impurities of
water8. Answer: set freezing points and boiling points
and divide into equal divisions9. Answer: Celsius, Kelvin, Fahrenheit10. Answer: Kelvin11. Answer: 0C12. Answer: 100C13. Answer: coldest possible temperature14. Answer: Celsius is –273.15C and Kelvin is 0 K.15. Answer: sensor, signal, responder16. Answer: thermocouple17. Answer: bimetallic strip18. Answer: recording thermometer19. Answer: infrared thermogram20. Answer: 96F
21. Answer: all substances are made of particles, constant motion, spaces, motion of particles is related to temperature
22. Answer: Joule23. Answer: high energy to low energy or hot to
cold24. Answer: the average speed of particles in
motion25. Answer: something’s ability to do work26. Answer: increase in volume27. Answer: decrease in volume28. Answer: warms and cools quickly29. Answer: warms and cools slowly30. Answer: liquid to solid31. Answer: solid to liquid32. Answer: gas to liquid33. Answer: evaporation34. Answer: sublimation35. Answer: stays constant36. Answer: evaporative cooling37. Answer: at the point where a substance
changes from one state to another, heat cannot be detected, on a graph it is represented by a
plateau (the particles are going through a rearrangement from a sold to a liquid to a gas OR a gas to a liquid to a solid)
37. Answer: electromagnetic radiation
38. Answer: radiation, convection, conduction39. Answer: behave like waves, can be absorbed or
reflected, travel at high speeds40. Answer: microwaves, x-rays, visible light, radio
waves, sunlight41. Answer: solid42. Answer: insulators43. Answer: metals44. Answer: the continuous cycle of warm air rising,
cooling and returning to the energy source45. Answer: furnace, stove, dryer, winds and
breezes46. Answer: energy source, direction,
transformation, waste heat and control system47. Answer: energy stored in food and fuels48. Answer: hydroelectricity49. Answer: car brakes, tires skidding, nail
pounding – anything related to friction50. Answer: energy that is harnessed from the
Earth’s surface51. Answer: energy from the sun52. Answer: through nuclear fission small amounts
of radioactive uranium is used to produce vast amounts of heat
53. Answer: active solar heating uses mechanical devices like fans to distribute stored thermal energy – heating that requires a mechanical device to carry heat to other parts of the building
54. Answer: passive solar heating uses the materials in the structure to absorb, store and release solar energy – direct heating by the sun’s rays, without fans, pumps or pumps to carry the heat to other parts of the building
55. Answer: windmills56. Answer: resources that once gone are gone
forever (takes a long period of time to replace)57. Answer: resources that can be recycled or
replaced
58. Answer: gases, such as carbon dioxide, that result from the burning of fossil fuels or wood; greenhouse gases prevent heat from leaving the atmosphere, increasing the temperature of the atmosphere
59. Answer: a method of energy conservation by which waste heat or energy from one industry is used by another
60. Answer: a warming of the environment as a result of human activities, such as burning of fossil fuels
61. Answer: carbon dioxide, sulfur dioxide, carbon monoxide
62. Answer: anything that takes up space, has mass and is made up of particles
63. Answer: NO64. Answer: gas65. Answer: liquid66. Answer: a material that is composed of only
one type of particle
