Thermodynamics Flashcards
Extensive properties
Change is seen as amount of sample changes
Ex. Delta h delta s delta g and delta e
State functions
An aspect of a chemical system
Pressure temp volume and number of atoms/mols
Quantities are made intensive properties when we define
The temp, pressure, mass and physical state of the substance
Standard state of a system
1 ATM, 25 degrees Celsius, 1 mole of compound
Delta H^o
Delta S^o
Delta G^o
The ^o means that
The system is at standard state and they are intensive properties
In a exothermic reaction delta h is
Negitive
Kinetic energy KE is
The energy that matter possesses because of motion
KE=
.5mv^2
Potential energy
Stored energy that may be released under the appropriate conditions
Specific heat of water
4.184J/g degrees celcius
Specific heat
The amount of energy required to raise the temp of a substance 1 degree Celsius
Dulong and Petit law
Specific heat X molar mass = 25J/mol*degrees Celsius
Specific heat is a ________ physical property of all elements and can be used to _________
Intensive
Identify substances
Heat energy (q) = (In terms of specific heat)
(Specific heat)(mass)(Delta T)
q is expressed in (unit)
Joules
First law of thermodynamics states
Energy is always conserved
Delta E =
q + w (Heat energy + work) or PEfinal - PEinitial (Potential energy)
q is positive in
Endothermic reactions
w is positive when
Work Is done on the system
w is negative when
Work is done by the system
Work is equal to
In terms of pressure
-P* Delta V
If volume increases in a system
Work is done by the system and w is negitive
When volume decreases
Work is done on the system and w is positive
Work is defined as
Force applied to an object as it moves a certain distance
