Chapters 14-15 Flashcards
Is air, glass, vacuum or wood the best insulator?
Vacuum
Heat transfer occurs due to direct contact with conduction, convection, heat flow or radiation?
Conduction
The method of heat transfer that does not require a medium is conduction, convection, heat flow or radiation?
Radiation
Conduction, heat flow, radiation, or thermal conductivity is defined as the amount of heat transferred from one end of a solid to the other per unit of time?
Heat flow
Condensation, freezing, melting or vaporization is the process which occurs when a substance goes from the gaseous to the liquid state?
Condensation
The —– law of thermodynamics is our basis for measuring temperature. (Zeroth, first, second, third)
Zeroth
For a given solid, the coefficient of area expansion is —– the coefficient of linear expansion. (Half of, the same as, two times, three times)
two times
The amount of heat that must be supplied to melt a unit of mass of a substance at its melting point is called the substance’s —–. ( latent heat, heat of fusion, heat of vaporization, heat of melting)
heat of fusion
The heat required to raise the temperature of one gram of water from 14.5 degrees celcious to 15.5 degrees celcious is one —–. (BTU, calorie, joule, kilocalorie)
calorie (cal.)
The heat required to raise the temperature of a body by one degree is called —–. (Heat capacity, one calorie, specific heat, stable equilibrium)
heat capacity
The unit of heat in the U.S. customary system is called the —–.
BTU
British thermal unit
The process of measuring temperature is called —–.
thermometry
At the boiling or melting point of a substance, a substance can absorb or give off heat respectively without changing its —-.
temperature
The transfer of thermal energy caused by a difference between the initial internal energies of town bodies is called —–.
Heat
One calorie is approximately —– joules.
4.184 joules
The study of the relationship between heat and work is called —–.
thermodynamics
A system sealed off from any energy exchange with its surroundings is called a(n) —– system.
isolated system
A process in which no heat enters or leaves a system while the system’s internal energy changes is called a(n) —– process.
adiabatic
A transfer of energy caused by a force operating over a distance is called —–.
work
A(n) —– process absorbs or releases heat without changing the temperature of the system.
isothermal
A(n) —– process has occurred when both the initial and final equilibrium states of the system are known, but the path the system took is not known.
irreversible
The concept of —– results from the second law of thermodynamics.
Entropy
True/False
The point at which a substance can exist in all three states of matter at the same time is the substance’s (triple point).
True
The (internal energy) of a system may be defined as the total molecular energy content of a physical system.
True
When a substance melts, it undergoes an (Exothermic) process.
Endothermic
The transfer of heat by moving material is called (radiation).
Convection
The ability of a material to conduct heat is called the material’s (thermal) conductivity.
True
The science of (thermometry) uses a calorimeter to measure the equilibrium temperature of a mixture.
calorimetry
Zero (celcious) is the lowest theoretically attainable temperature.
Kelvin
In an isolated system, the direction of spontaneous change is always toward (less) entropy.
greater
One kilocalorie equals (one thousand) calorie(s).
True
(Caloric) was an imaginary liquid used to explain how heat transferred from one body to another.
True
The heat required to raise the temperature of a unit mass by one degree is called (specific heat).
True
(Thermal energy) flows spontaneously from hot to cold objects.
Heat
The amount of work equal to a unit of heat is called the (mechanical equivalent of heat).
True
Equations
The first law of thermodynamics
Delta E(int) = Q - W
The ideal gas law
PV=nRT
n= number of moles of the gas
R= is the universal gas constant 0.0821 Liter• atm
—————
Kelvin• mol
Determines the change in entropy of a system
The second law of thermodynamics
Delta S = Q
——
T
T= in Kelvins
Short answer
When is any system of bodies at thermal equilibrium ?
Any system of bodies is said to be at thermal equilibrium when the bodies have the same thermal energy and no heat transfer occurs.
Give one formulation of the second law of thermodynamics
In an isolated system, the direction of spontaneous change is always toward greater entropy.
Problems
See 41 - 45
T(C)= T(K)-273.15
