THERMODYNAMICS Flashcards
A porton of the universe which can be isolated physically or mentally in order to be studied
System
The adjacent portions of the universe outside such isolate entity being studied
Surroundings
Energy in Motion
Kinetic
Energy at Rest
Potential
Describes a configuration of minimum energy
Stable
Describes a configuration of maximum energy capable of spontaenous cange
unstable
Systems naturally (avoid, tend) configurations of min. energy
Tend to
State that is neither stable nor unstable
Metastable
the study of motion such as projectiles or falling rock
Mechanics
deals with the energy of heat and work
Thermodynamics
Measure of Energy transfer that occur when an object is moved over at as distance by external force
Work
Measure of Energy content/Driving force of chemical systems or Spontaneity of Reaction
Gibbs Free Energy
Mathematical Expression of Gibbs Free Energy
G = H - TS
(H-Enthalphy
T- emp in K
S - Entropy)
The measure of Heat Content of a system per unit mass volume
Internal Energy + (Volume*Pressure)
Enthalpy
The measure of thermal energy per unit temp unavailable for work or
measure of the molecular randomness of a system
Entropy
Between solid, Liquid and Gas, which has the greatest entropy?
Gas
Stable Systems have (Min, Max) Gibbs Free Enery
Minimum
If ?G > 0 (Positive)
Backward Reaction (Endergonic)
Reactant have lower total free energy than products
If ?G < 0 (Negative)
Forward Reaction (Exergonic)
Products have lower totral free energy than reacttans
Gibbs free energy of a mineral in reference state
0
A property that is dependent upon the QUANTITY of te material in the system
Extensive Variable
Independent upon the quantity
Intensive Variable
The amount of heat required to raise 1 mole of a the substance 1deg cel
Heat Capacity
Constant Temperatures
Isothermal
Constant Pressure
Isobaric
If ?G = 0
Sustem is in equilibrium and in a phase diagram lies in the equilibrium curve
Principle stating that in any distrubance in a system in dynamic equilibrium, the system will react in a fashion to mitigate or counteract the change
If a chane is imposed on a system at equilbrium, the position of the equilibrium will shift in a direction that tends to resuce such change
Le Chatelier’s Principle
An equation that gives the slope of the equilibrium curve in a binary phase diagram
Clapeyron Equation
Temperature is proportional to Enthalpy and Entrophy
Pressure is inversely proportional to Volume
Solid Lowest Entalphy and Entropy
Lowest Molecular Volume
Gases highest
If ?H < 0 (Entalphy is Negative)
Exothermic - Palabas ang Heat
If ?H > 0 (Entalphy is Positive)
Endothermic - papasok ang heat
If ?H < 0 , ?S > 0, the reaction is
Fowardm Spontaneous at all T
When will reaction be non spontaneous at all T
if enthalpy is positive and entropy is negative
If both Enthalpy and Entropy is positive
Reaction will be spontaneous at high T
If both Enthalpy and Entropy is negatvie
Reaction will be spontaneous at low T
Matter and Energy can Pass
Open
Matter can’t but energy can pass
Closed
Both Matter and Energy cant pass
Isolated
Solid - Gas
Sublimation
Gas - Solid
Deposition
Gas - Plasma
Recombination
Plasma - Gas
Ionization
Liquid - Gas
Evaporation
Gas - Liquid
Condensation
Liquid - Solid
Freezing
Solid - Liquid
Melting
Gibss Phase Formula
F = C-P+2
At what values of F will chemical reactions generally occur
F<2
At what value of F will continuous reactions occur and take place over range of temp in constant pressure
F>0
At what value of F will Discountinuous reaction occur and thus cannot involve compostional or temp changes and the entire reaction must occur at single temp
F=0
Represents the mixture that has the lowest freezing Pt
Eutectic
Represents the last solid to form when freezing
Eutectic
weight loss that occurs when poweered sample is heate to about 800 deg cel at w/c pt all the remaining volatiles are released and is a quantitative indicator of secondary hydrous alteration
Loss of Ignition (LOI)
Shows relative pressure at the time of melting and is useful in assessing silica saturation a.k.a Cation Norm
CIPW (Cross Iddings, pearson, Washington
Volume % of the minerals seen
Mode
Calculated Idealized Mineralization or
A set of hypothetical minerals that could crystallize from a magma with the same chemical composition as the rock
Norm
MgO versus selected Major Oxide Elemens
Fenner Diagram
SiO2 vs selceted Major Oxides and oldest Bivarate Diagram
Harker Diagram
Alkali vs silica for Volcanic Rocks (X - SiO2 , Y - Na2O+K2O)
TAS
Differentiate Ultramafics Komatiite and Picrite
Komatiite
>18% wt MgO
Has characteristicallY Spinifex Texture w/c implies veryvery fast cooling from very very hot magma
almost eclusively formed in Archaean
Picrite
Have lots of Olivine occurs as penocryst or xenocryst
15% wt MgO
a diagram w/c further subdivides the subalkaline series into Tholeeitic and Calc Alkaline
AFM
A = Na2O+ K2O
F = FeO + Fe2O3
M = MgO
Where would MORB plot in AFM?
Near tholeiitic siginifying Fe enrichemnt
Calc alkaline are only found in
Subduction zones due to water conent which would change the sequence of crystallizing minerals and delays crystallization of Plagioclase
