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## Ignore words

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temperature
A measure of the average energy of motion of the particles of a substance.
thermal expansion
The increase in volume of a substance due to an increase in temperature
Celsius
A temperature scale with the melting point of ice at 0 degrees and the boiling point of water at 100 degrees.
Fahrenheit
A temperature scale with the melting point of ice at 32 degrees and the boiling point of water at 212 degrees.
Kelvin
A temperature scale with the lowest possible temperature at the zero point, which is called absolute zero.
expansion joints
space between solid objects like sidewalk slabs that allow room for expansion (when heated) and contraction (when cooled)
thermostat
a device used to control the temperature
bimetalic strip
a strip made of two different metals that expand at different rates
hot-air balloon
rises because the thermal expansion of heated air reduces the density of the balloon
heat
energy transferred between samples of matter because of a difference in their temperature
thermal energy
a hot coffee mug
convection
the process whereby heat is transferred by the mass movement of molecules from one place to the other
energy that is radiated or transmitted in the form of rays or waves or particles
Specific Heat
Amount of heat needed to raise the temperature of 1kg of material 1 degree Celsius.
thermal conductor
a material through which energy can be transferred as heat
thermal insulator
a material that reduces or prevents the transfer of heat
Conduction
the direct transfer of heat or sound from one substance to another substance that it is touching
state of matter
a physical property that describes matter as a solid, liquid, or gas
change of state
The conversion of a substance from one physical form to another
Calorimeter
A device in which heat transfer is monitored by recording the change in temperature that it produces, then using q = C₋cal∆T, where C₋cal is the heat capacity of the calorimeter.
Solid
Solid, liquid, or gas? The particles may appear packed close together but there is space between then and are in constant motion.
liquid
a substance in the fluid state of matter having no fixed shape but a fixed volume
gas
a fluid in the gaseous state having no fixed shape nor volume
chemical change
irreversible change that will change the identity of the substance
insulation
a material that reduces or prevents the transmission of heat (or sound or electricity)
Heat Engine
a machine that transform heat into mechanical power: steam heating.
passive solar heating
the use of sunlight to heat buildings directly
combustion
a process in which a substance reacts with oxygen to give heat and light
compressor
a mechanical device that compresses gasses
refrigerant
a substance used to provide cooling (as in a refrigerator)