Module5 : Electrochemistry
Lecture 21 : Review Of Thermodynamics
 
A change in enthalpy resulting from a change in temperature at constant pressure is given by
  
    H = Cp d T (21.12)
Measurement of heat capacities of substances constituted a major part of the early development of thermodynamics. It enabled the estimation of H and U for physical and chemical changes.
 
For an ideal gas, the equation of state (a relation between P,V and T for a given substance) is PV = nRT where n = number of moles of the gas, R = gas constant and T the absolute temperature. For a monatomic ideal gas, C V = 3/2 R and Cp = 5/2 R. In general, heat capacities do have strong temperature dependence and mild pressure dependence
 


 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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