Science chapter 9 test - 9th
a quantity of thermal energy that flows from one system to another, resulting in a change of temperature or state. Measured in Joules.
heat
the amount of thermal energy that an entire object must gain or lose to change its temperature by 1 degree C. Heat capacity depends on the mass and thermal properties of the substance in the object.
heat capacity
the amount of thermal energy absorbed per gram as a pure solid melt (fuses) at its melting point. The same amount of heat per gram must be released to freeze the substance the substance.
latent heat of fusion
Compare and contrast heat and thermal energy
Heat: a quantity of thermal energy that flows from one system to another, resulting in a change of temperature or state. Measured in Joules. Thermal energy: the average sum of the kinetic energies of all the particles in an object. Directly proportional to the temperature of the object
who's theoretical zero point is absolute zero. Its single fiducial point is the triple point of pure water. One kelvin is the same size unit as one degree Celsius.
Kelvin scale
the amount of thermal energy absorbed per gram as a pure liquid vaporizes. The same amount of heat per gram must be released to condense the vapor to a liquid.
Latent heat of vaporization
a model of heat as a material fluid that flows from hot to cold objects. When scientist discovered that it could not explain certain observations, they replaced it with the kinetic-molecular model of thermal energy and heat.
Caloric Theory
Describe the flow of thermal energy
Thermal conduction occurs when thermal energy moves through matter as particle kinetic energy is transferred through collisions.
describe how thermal energy affects matter volume and its ability to allow electricity to pass through it
Thermal energy affects matter volume because if you have an ice cube that is melting, the volume of the ice cube obviously changes to a different state. Likewise, if water is freezing, it will change its volume by becoming hard and more solid.
Comparing and contrast thermal and internal energy
Thermal energy: the average sum of the kinetic energies of all the particles in an object. Directly proportional to the temperature of the object Internal energy: the sum of the kinetic and potential energies of particles together with the energies needed to assemble the particles into structured matter.
summarize the physical properties of insulators and conductors
Thermal insulators: Materials that resist the flow of thermal energy. Atoms can be bonded closely together or in a weblike structure. Thermal conductors: heat can easily flow through conductors because they heat up quickly...
the study of thermal energy, heat, and their useful applications
Thermodynamics
a temperature scale with fiducial points at the freezing point (0) and the boiling point (100) of pure water at 1 atm of pressure
Celsius scale
Describe the 3 methods of heat transfer and give examples
Conduction: when two objects touch, one another, they exchange thermal energy so that the warmer side begins to cool, and the cooler side begins to heat until they have both reached mechanical equilibrium. Convection: thermal energy carried form one location to another by a fluid, like hot water boiling to cook noodles Radiation: the sun giving of thermal energy while not giving off heat through a liquid or by touch
Describe how Count Rumford discovered a problem with the caloric theory
Count Rumford discovered a problem with the caloric theory by observing how cannons fired without the cannonball in them were gaining more thermal energy than those fired without the cannon balls. It was also disproved through observing that a dull bit could generate more heat than needed to melt the entire cannon barrel. His observation helped bring about the end of the caloric theory.
a temperature scale with fiducial points at the freezing point (32) and the boiling point (212) of pure water at 1 atm of pressure
Fahrenheit scale
Identify the fiducial points for each temperature scale.
Fahrenheit: Boiling (212F) and freezing (32F) points of water. Celsius: Boiling (100C) and freezing (0C) points of water. Kelvin: the triple point of water
compare and contrast Fahrenheit, Celsius, and Kelvin scales
Fahrenheit: Is a different unit than Celsius and Kelvin. Celsius: Fahrenheit and Celsius both use the degree symbol. Kelvin: one unit in Celsius is the same as one unit in Kelvin.
a measure of the average kinetic energy of the particles in a substance; the hotness or coldness of an object, measured in degrees
Temperature
describe how thermometers work
When thermal energy enters a thermometer, the indicated temperature rises. When it leaves the thermometer, the indicated temperature drops.
one of three methods of heat transfer from a hotter to a cooler object, conduction involves direct contact
conduction
One of three methods of heat transfer from hotter to cooler locations. Convection involves the flow of a fluid within a gravitational field, as warmer, less dense fluid is displaced upward by descending, cooler fluid.
convection
compare and contrast heat capacity and specific heat
heat capacity: the amount of thermal energy that an entire object must gain or lose to change its temperature by 1 degree C. Heat capacity depends on the mass and thermal properties of the substance in the object. Specific heat: the amount of thermal energy 1 g of a substance must gain or lose to change its temperature 1 degree Celsius.
one of the three methods of heat transfer from hotter to cooler locations involving radiant energy. The process of energy or particles moving directly away from the source. It also refers to the nuclear particles or electromagnetic waves themselves that are in such motion.
radiation
every natural process moves toward a condition of lowest usable energy and highest entropy.
second law of thermodynamics
the amount of thermal energy 1 g of a substance must gain or lose to change its temperature 1 degree Celsius.
specific heat
Explain temperature change in terms of the kinetic-molecular theory
temperature change in matter is not a material fluid but a form of energy.
summarize the development of the theory of thermal energy
the theory of thermal energy went from a caloric theory of heat which proved true for most situations but a select few proved that theory wrong. Next the study of thermodynamics came along which is what is used today and evolved from Carnot's work.
give examples of thermometric properties
volume of a liquid, length of a solid, gas pressure, electrical resistance and electromotive force