Planning Guide
Unit 2: Matter & Heat
Contents
Overview
This unit deals with the properties of matter and the transfer of
energy. We use the kinetic theory to explain the different states
of matter (solid, liquid and gas) and how the movement of
particles contributes to expansion and changes between phases. We
also investigate heat capacities of different materials. Our
study of heat transfer by conduction, convection and radiation
provides an introduction to Unit 3 in which we study radiation
and waves.
Shopping List
Measuring
Instruments
The following measuring devices will be needed for the
experiments in this unit. (You should already have the first 5
items.)
Graduated Cylinder
Vernier Caliper
Eye protection & hand protection: Safety glasses can be purchased from most hardware stores. These will be needed during many of the experiments and hands-on activities. Cotton gloves should be used whenever items are likely to heat up. Rubber or vinyl gloves should be used whenever chemicals are handled.
The following suppliers offer many of the laboratory items at prices that appear to be reasonable. Unless otherwise stated, the prices given above are typical of those provided by the suppliers. Prices and availability can vary and the prices given above can only serve as a very rough guideline.
http://www.hometrainingtools.com
http://www.freyscientific.com
Additional
Items
In addition to the items listed above, various low-cost (or
common household) items will be needed for the experiments, hands-on
activities and projects listed below. These can be purchased,
assembled or obtained by dismantling old or discarded items.
Hands-on Activities
Lesson 2.1 Atoms
1. See how many times you can cut
a piece of paper in half
2. Show that there is a limit to the number of times that we can
cut a piece of paper in half.
Lesson 2.2
1. Boil water starting with
crushed ice.
2. Show that the temperature of a substance remains constant
while it changes from solid to liquid and from liquid to vapor.
Lesson 2.3 Solids
1. Compare the ways in which
rubber, metal balls and marbles bounce when they collide with
each other.
2. Measure the density of a metal cube or rectangular object
Lesson 2.4 Liquids
1. Use a Eureka can to measure the
volume of water displaced by a submerged object. Weigh the object
and determine its density.
2. Weigh the object in air and in water and calculate its density.
Lesson 2.5 Gases
Lesson 2.6 Heat Capacity
This lesson deals with energy and the amount of energy needed to
increase the temperature or change the state of a material. On
completion of the lesson, you should be able to discuss specific
heat capacities, latent heats of fusion and latent heats of
vaporization. You should be able to use specific heat capacity
data to estimate temperature or energy changes. You should also
be able to estimate the amount of energy needed to change a
particular amount of solid to liquid or liquid to gas.
Lesson 2.7 Expansion
1. Bimetallic strip: Open a
thermostat or temperature-indicating device that uses a
bimetallic strip and show how the strip bends when heated.
2. Hold the ends of rods or pipes made from different metals in a
flame (gas cooker) and compare the rates at which heat is
transferred through the different materials. See how the
thickness of the material affects the rate of heat transfer.
Lesson 2.8 Conduction & Convection
1. By holding two objects – a piece of wood and a metal object - try to estimate the difference in temperature between a piece of metal at room temperature and a piece of wood that has been placed in a refrigerator for some time. The wood will quickly "feel" warmer because it has a much lower thermal conductivity that the metal.
Lesson 2.9 Evaporation
1. Wrap a small piece of cloth on
a thermometer bulb, moisten the cloth and observe the change in
temperature when it is placed in front of a fan
2. Place a piece of wet cloth inside a clear plastic bag, put a
piece of wire inside the bag to provide an air space in the bag.
Place the bag in the sun and observe the provess of evaporation
from the cloth – and condensation on the inside of the bag.
Lesson 2.10 Refrigeration
1. Measure the temperature of the
air in a container (or the surface of the container) Use a pump
to compress air into a container. Show that the temperature
increases when the air is compressed.
2. Identify the different components o a refrigerator or air
conditioner and discuss their design and operation.
Lesson 2.11 Thermodynamics - 1
1. Observe the operation of an
external combustion engine such as a steam engine.
2. Make a model steam turbine.
Lesson 2.12 Thermodynamics - 2
1. Observe the operation of an
internal combustion engine such as a lawnmower engine.
2. Open up the engine to see the parts.
Physics Labs: Experiments
Physics Lab 2.1 Hydrogen
1. Use hydrochloric acid and granulated zinc in a polyester soda
bottle to make hydrogen gas
2. Fill two balloons – one with hydrogen and the other with
air. Allow to stand for 2 or 3 hours and compare the differences
in size.
Materials & Equipment: Glass beaker / jar / container,
polyester soda bottle, granulated zinc, hydrochloric acid (Muratic
acid), balloons, PVC gloves
Physics Lab 2.2 States of
Matter
Demonstrate the energy changes that occur when a liquid
solidifies. Naphthalene (moth balls) or candle wax can be used
for this experiment.
Materials & Equipment: 3 or 4 moth-balls (Alternatively:
some candle wax), Thermometer small glass or aluminum container,
hot plate, stopwatch, graph paper
Physics Lab 2.3 Elasticity
Illustrate the
relationship between the extension of a spiral spring and the
force acting on the spring. We also increase the force on the
spring to exceed the elastic limit.
Materials & Equipment
Steel wire, dowel, soda can, small spring, needle, straw
A number of articles with similar weight. (e.g. coins, marbles,
lead weights etc.)
Physics Lab 2.4 Eureka
1. Use a Eureka can to
determine the densities of 2 or 3 objects.
2. Estimate density by measuring the buoyant force on a submerged
object. From this we determine the mass of liquid that has been
displaced and the volume of the object.
Materials & Equipment: Eureka can, 2 or 3 irregularly
shaped objects, spring scale, measuring cylinder.
Physics Lab 2.5 Gases
1. Use a garbage bag,
a piece of aluminum foil and some fuel gel to make a hot air
balloon
2. Demonstrate the Venturi effect using a drinking straw
Physics Lab 2.6 Heat Capacity
& Latent Heat
1. Use a small
immersion heater to heat a known quantity of water in an
insulated container and plot the increase in temperature of the
water with time. The immersion heater should provide a constant
supply of energy at the element’s Wattage rating. Calculate
the specific heat capacity of water.
2. Use the immersion heater to boil the known quantity of water
for a fixed period of time. Determine the latent heat of
vaporization of water from the amount of water left in the
container after the boiling process has been completed.
Physics Lab 2.7 Heat Capacity
of Steel
Determine the specific heat capacity of one material by allowing
it to gain energy from a known amount of water. The two materials
reach thermal equilibrium in an insulated container and the
energy lost by the water is assumed to be gained by the second
material.
Physics Lab 2.8 Vernier
Demonstrate the use of
a Vernier scale in obtaining an accurate estimate of the fraction
of a graduation when the length of an object is measured.
Activity: Make a model of a Vernier scale
Materials
Cardboard, Ruler
Physics Lab 2.9 Expansion
Measure the
coefficient of thermal expansion of a metal by heating a metal
pipe with steam and measuring the increase in length.
Equipment
Water boiler (Steam generator), vernier calipers, protractor,
hose – neoprene
Metal pipe about 2 meters long (copper, steel, aluminum),
thermometer, clamping device
Wooden skewer or thin dowel with pointer attached.
Physics Lab 2.10 Conduction
Illustrate some
differences in the thermal conductivities of different metals.
Use bars or pipes made from different metals, and wax to attach
marbles to the metal objects at different intervals along its
length. Heat each metal objects at one end using the same heat
source. Measure the time taken for each marble to drop when the
wax holding it to the metal melts. This will provide an
indication of the rate at which heat travels along the length of
the object.
Physics Lab 2.11 Solar Still
Illustrate evaporation
and condensation.
Design, construct and test a solar distillation unit. Measure the
amount of water that it produces each day and identify the
factors that may contribute to a more efficient design.
Equipment
Anything you can use to make a solar still: Plastic bottles,
cans, plastic bags etc.
Physics Lab 2.12 Solar Radiation