Concepts students need to know
Ch 21
Temperature—how hot or cold something is compared to some ___________.
Celsius scale—freeze 0 degrees and boiling __________degrees.
Fahrenheit-- freeze 32 and boil ________ degrees.
Kelvin -- _________ at 273 and boil at 373
Absolute zero (0 Kelvins) a substance has no _________ energy.
Temperature is ___________ to average kinetic energy
Heat—the energy that transfers from one object to another because of ______________
difference.
Heat is internal energy.
 Thermal contact—heat flow from one object to another in ______________.
 Heat never flows on its own from a __________ substance to a hotter substance.
 Thermal equilibrium—When objects in thermal contact are the same__________.
 A thermometer shows its own ____________. Why? _____________________.
 If a thermometer is too large, it will __________ the material being measured.
 Internal energy—a substance does not contain heat, it contains _________energy.
 The grand total of all energy inside a substance (jostling, spinning, potential
energy) is ___________ energy.
Measurement of heat—To quantify heat, we must specify the ________ and kind of
substance affected.
 Calorie—the amount of heat required to raise the temperature of 1 gram of
_____________ by 1 degree C.
 Kilocalorie—__________ calories
 1 calorie—_________ joules
Specific heat capacity the amount of heat required to raise the ___________ of a unit
mass of a substance (1 gram) by one degree C
 --Different materials have different capacities for storing ___________ energy.
 Q = mcΔT
Solve 5-10 problems.
Specific heat capacity of water—water takes a __________ time to heat up and a long
time to cool. This is useful in cooling and heating systems. Also living close to an ocean
or lake allows for __________ days and ___________ nights.
Thermal expansion—all forms of matter expand when heated and contract when
_______-.
Metal expansion-- techniques for machines, sidewalks, bridges, jar lid, etc.
 Bimetallic strip-- show sample

Thermostat
Expansion of water—water is the most ___________ at 4 degrees C.
 Only when all the water in a pond is 4 degrees C can any water be cooled
to 3 degree, 2 degree, 1 degree etc. Water at 4 degree C __________ to
the bottom. This allows ______ to form at the top of the lake and allows
fish to live through the winter.
Chapter 21 Review questions # 1-15.
Ch 22
Heat transfer Conductors—Materials that ________ heat well. (solids)
--Collisions between atoms and molecules because of _________bound electrons.
Why do metals feel colder? __________________________________________
Insulators—poor ________ conductors—wood, polystyrene, air.
_________ is simply the absence of heat.
 Convection—occurs in all ________.
 Radiation—Suns heat transmitted to earth (or other planet), does not need
a _________. Energy can be transmitted through a vacuum. Radiant
energy is in the form of ______________waves. (includes radio waves,
microwaves, infrared, visible light, ultra violet, x rays and gamma rays).
All objects continually emit radiant energy. Low temperature objects emit
_________ waves (low frequency) and high temperature objects emit
short (_________ frequency).
At 500 degrees C objects ________ red light, at 1200 degrees C objects
emit white “hot” light.
Absorption and reflection are _________ processes.
A good absorber is dark and does not _________ any radiant energy.
Good reflectors are light colored and therefore are cooler in the summer (does not
___________).
Good absorbers are good ____________ (coffee pots).
Good reflectors are poor emitters.
Newton’s Law of cooling—the rate of cooling is proportional to the ____________
difference between an object and its surroundings. (works for heating also).
Global Warming and ______________effect—[high temperature things radiate short,
high frequency waves and low temperature things radiate long, low frequency waves].
Radiation from the sun (short wavelength) easily penetrates earth atmosphere are
absorbed by earth and cool, earth radiate cooler, ____________ wavelength radiation
cannot penetrate earth atmosphere and; therefore, are trapped and warm the earth.
Present earth temperature average from 19 degrees C to 27 degrees C.
Review questions P 333 # 1,2,3,4,5,6,8,10,11,14,15,16,19,20.
Concept Dev 23.1