MODULE 5: ENERGY AND LIFE Flashcards
deals with the relationships between heat and other forms of energy
THERMODYNAMICS
Laws of Thermodynamics
First Law of Thermodynamics
Second Law of Thermodynamics
Third Law of Thermodynamics
Zeroth Law of Thermodynamics
Who first used the word thermodynamic?
William Thomson (Lord Kelvin)
therme (Gr.) means
heat
dynamis (Gr.)
power
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
What cross into the system?
HEAT
What cross out the system?
WORK
Closed System
With heat
With work
No mass
Open System
With heat
With Mass
With Work
Isolated System
No Heat
No Mass
No Work
Adiabatic System
No Mass
No Heat
With Work
present status of the system described in terms of macroscopic properties, such as pressure, temperature, volume, no. of moles
STATE OF THE SYSTEM
Characteristics by which the physical condition of the system is described
PROPERTIES OF THE SYSTEM
Properties of the system that depend on mass or quantity of the system
Extensive Properties of the System
Properties do not depend on the quantity of matter of the system
Intensive Properties of the System
Extensive Properties
Mass, Volume, Enthalpy, Entropy, Internal Energy
Intensive Properties
temperature
freezing point
boiling point
specific volume
density
isothermal
isobaric
isochoric
constant temperature
constant pressure
constant volume
state or condition with no spontaneous changes with respect to time
equilibrium
property of an object related to the average kinetic energy of atoms and molecules in that object
TEMPERATURE
heat exchange happens in
thermal contact
no net exchange of energy
thermal equilibrium
device calibrated to measure the temperature of an object
thermometer
Scale used mostly in scientific and technical work
KELVIN
What are the major difference between the temperature scales
size of their basic unit (degree)
temperature that refers to zero
lower limit of temperature which all the energy possible has been removed from the molecules
ABSOLUTE ZERO
Conversion of Celsius to Fahrenheit
- F = 9/5 (C) + 32
Conversion of Fahrenheit
- C = 5/9 (F - 32)
Conversion to Kelvin
K = C + 273.15
If objects A and B are separately in thermal equilibrium with a thrid object C, then A and B are in thermal equilibrium with each other.
ZEROTH LAW THERMODYNAMICS
transferred between a system and its environment because of temperature difference that exists between them
HEAT
Temperature difference is also called
TEMPERATURE GRADIENT
BASIC UNIT OF HEAT
JOULE
Amount of heat that it takes to increase the temperature of 1g of water 1C degree at 15 degree Celsius.
Calorie
1 cal = Joules
4.186 Joules
1Kcal = Joules
4186 Joules
Amount of heat transferred (Q)
Q = mcΔT
m = mass
c = specific capacity
ΔT = Final T. - Initial T.
Methods of Heat Transfer:
Two objects that are touching each other. Collisions between small particles allow fast moving, or vibrating, particles to give some of their microscopic kinetic energy to slower particles.
CONDUCTION
Methods of Heat Transfer
caused by moving fluids, where particles can mix together, move faster, and spread out, thus distributing their thermal energy
CONVECTION
occurs without the movement of matter; made of EM waves given off by moving particles; absorbed by materials
RADIATION
TRUE OR FALSE
ALL TEMPERATURE CHANGES NEED NOT BE DUE TO HEAT ALONE
TRUE
TRUE OR FALSE
ALL HEAT INTERACTION NEED NOT RESULT IN CHANGES IN TEMPERATURE
TRUE
