# Physical Science Chapter 9

 an obsolete model of heat that considered heat a material fluid that flowed from hot to cold objects caloric theory the sum of all forms of particle energy in a substance internal energy a piston engine containing a working gas that is transferred between hot and cold heat exchangers to move the pistons. The source of heat comes from outside the engine. Stirling engine a measure of the average kinetic energy of the particles in a substance; the hotness or coldness of an object, measured in degrees. temperature dimensional unit of temperature whose magnitude depends on which system is being used degree an instrument that uses a thermometric property to measure and display temperature thermometer any property of matter that varies in proportion to changes in temperature thermometric property fixed, precise, and easily reproducible values in a dimension used to calibrate a measuring scale in Fahrenheit and Celsius temperature scales they are the boiling and freezing points of pure water at 1 atm of pressure fiducial point a temperature scale with fiducial points at the freezing point (32 degrees) and the boiling point (212 degrees) of pure water at 1 atm of pressure Fahrenheit scale a temperature scale with fiducial points at the freezing point (0 degrees) and the boiling point (100 degrees) of pure water at 1 atm of pressure Celsius scale the pressure and temperature conditions at which the solid, liquid, and gaseous phases of a substance simultaneously exist in a stable condition triple point the absolute temperature scale, whose theoretical zero point is absolute zero. Its single fiducial point is the triple point of pure water (273.16 K) One Kelvin is the same size unit as one degree Celsius Kelvin scale a thermal property of most materials in which length or volume increase in proportion with increasing temperature thermal expansion a quantity of thermal energy that flows from one system to another heat (Q) law stating that every natural process proceeds toward a condition of lowest usable energy and highest entropy second law of thermodynamics the measure of a system's randomness or disorder entropy (S) the flow of thermal energy from a hotter to a cooler object by direct contact conduction the condition of a system that is at the same temperature as it surroundings so there is no net flow of thermal energy thermal equilibrium a material through heat and electricity easily flow conductor the transfer of thermal energy from one location to another through the movement of matter convection a flow of matter in a fluid as warmer, lower density fluid is dispaced upward by cooler, denser fluid flowing downward. With a continuous heat input, the flow follows a cyclical path. It can occur only in a gravitational field. convection current nuclear particles or electromagnetic waves that radiate away from their sources; a method of heat transfer through radiant (electro-magnetic) energy radiation a material that does not easily conduct thermal energy or electricity, a poor conductor with tightly bound valence electrons insulator the amount of thermal energy an entire object must gain or lose to change its temperature 1 degree C. Heat capacity depends on the mass and thermal properties of the substance(s) in the object heat capacity (C) the amount of thermal energy 1 g of a substance must gain or lose to change its temperature 1 degree C. specific heat (Csp) a device that measures thermal energy transfer between objects within a chamber insulated from its surroundings calorimeter the amount of thermal energy absorbed per gram as a solid melts (fuses) at its melting point. the same abount of heat per gram must be released to freeze the substance latent heat of fusion (Lf) the amount of thermal energy absorbed per gram as a liquid vaporizes. the same amount of heat per gram must be released to condense the vapor to a liquid. latent heat of vaporization (Lv) Authorbarbarad ID45943 Card SetPhysical Science Chapter 9 Descriptionvocabulary for Physical Science Chapter 9 Updated2010-10-29T18:14:20Z Show Answers