module 5 Flashcards
study of heat in motion
thermodynamics
branch of physics that deals with the relationships between heat and other forms of energy
thermodynamics
quantity of fixed mass under investigation
thermodynamic system
everything external to the system
surroundings
interface separating system and surroundings
system boundary
combination of system and surroundings
universe
2 important interactions between the system and its surroundings
heat can cross into the system
work can cross out of the system
3 types of thermodynamic system
closed system
open system
isolated system
the system of fixed mass across the boundary of which no mass transfer can take place
closed system
system across the boundary of which transfer of both mass as well as energy can take place across the boundary
open system
system in which both the mass as well as energy content remains constant
isolated system
a system which is not influenced by its surroundings
isolated system
is thermally isolated from its surroundings; there is no exchange of heat or matter but it is possible for system to do work on its surroundings
adiabatic system
present status of the system described in terms of observable macroscopic properties such as pressure, temperature, volume, and no. of moles
state of the system
characteristics by which the physical condition of the system is described
properties of the system
2 types of system properties
extensive and intensive
depends on the mass or quantity of the system
extensive properties of the system
mass, volume, enthalpy, internal energy, entropy
extensive properties of the system
do not depend on the quantity of matter of the system
intensive properties of the system
freezing point temperature, boiling point, temperature of the system, density
intensive properties of the system
state or condition in which no spontaneous or changes are observed with respect to time
equilibrium
a succession of changes of state
process
constant temperature
isothermal
constant pressure
isobaric
constant volume
isochoric
a property of an object related to the average kinetic energy of atoms and molecules in that object
temperature
two objects are in __________ if energy can be exchanged between them or there is energy transfer between them
thermal contact
two objects are in _______ if they are in thermal contact and there is no net exchange of energy
thermal equilibrium
a device calibrated to measure the temperature of an object
thermometer
temperature scales
fahrenheit scale
celsius scale
kelvin scale
is a lower limit of temperature which all energy possible has been removed from the molecules
absolute zero
if the objects A and B are separately in thermal equilibrium with a third object C, then A and B are in thermal equilibrium with each other
zeroth law of thermodynamics
the energy that is transferred between a system and its environment because of temperature difference that exists between them
heat
temperature difference is also called a
temperature gradient
basic unit of heat
joule (J)
amount of heat that it takes to increase the temperature of 1 g of water 1C and 15C
calorie (Cal)
amount of heat transferred is determined using this expression
Q= mc△T
Q= amount of heat transferred
m= mass of the object
c= specific heat of the substance
△T= change in temperature
indicates that object gained thermal energy from its surroundings; this would correspond to an increase in temperature
positive Q
indicates that the object released thermal energy to its surrounding; this would correspond to decrease in temperature
negative Q
3 heat transfer mechanisms
- conduction
- convection
- radiation
occurs between objects that are touching each other
conduction
heat transfer caused by moving fluids
convection
occurs without movement of matter
radiation
↑ temperature
↑ metabolism
↓ temperature
↓ metabolism
