absolute zero The temperature at which substance has no kinematic energy per particle (thermal) to give up. This temperature corresponds to 0 K, or to - 273 degrees Celsius.
bimetallic strip - Two strips of different metals, such as one of brass and one of iron, welded or riveted together into one strip. Because the two substances expand at different rates, when heated or cooled the strip bends.
calorie - A unit of heat. One calorie is the heat required to raise the temperature of one gram of water one Celsius degree. One Calorie is equal to one thousand calories and is the unit used in describing the energy available from food.
Celsius scale - A temperature scale with 0 as the melt-freeze temperature for water as the boil- condense temperature of water at standard pressure.
Fahrenheit scale - The number 32 is assigned to the freezing point of water, and the number 212 to the boiling point of water.
heat - Energy transfer via random molecular motions, resulting in gain or loss of internal energy.
internal energy - The total energy stored in the atoms and molecules within a substance.
Kelvin scale - A temperature scale whose zero is the temperature at which it is impossible to extract any more internal energy from a material. 0 K = -273 degrees Celsius. There are no negative temperatures on the Kelvin scale.
Kilocalorie - A unit of heat. One kilocalorie equals 100 calories, or the ammount of heat required to raise the temperature of one kilogram of water by 1 degree Celsius.
specific heat capacity - The quantity of heat required to raise the temperature of a unit mass of a substance by one degree Celsius. Often simply called "specific heat" or " heat capacity."
temperature - The property of a material that tells how warm or cold it is relative to some standard. In an ideal gas, the molecular kinetic energy per molecule.
thermal contact - The state of two or more substances in contact such that is possible for heat to flow from one object or substance to another.
thermal equilibrium - The state of two or more objects or substances in thermal contact when they have reached a common temperature.
thermostat - A type of valve or switch that responds to changes in temperature and that is used to control the temperature of something.