《物理化学 Physical Chemistry》课程教学资源（英文版）The First Law（The Machinery）

The first law The machinery C Stephen L. Davis, 2003

The First Law The Machinery © Stephen L. Davis, 2003

Exact differentials ifz= f(, y)is an exact differential Bf dx af dy Ox) dz dX

Exact Differentials dx dy dz if z = f(x, y) is an exact differential, dz = f x dx f y dy y x           +      

Internal Energy Changes U=/ oU + T du=Id+ cr dt where I=0 for an ideal gas

Internal Energy Changes dU U V dV U T dT dU dV C dT T V T V T =       +       = + =      where  0 for an ideal gas

Thermodynamic ea'n of state P

Thermodynamic Eq’n of State p T p T V T −         =   

Expansion Coefficient tIny △全F△T, assuming constant a orlm(/7)=∫ad7

Expansion Coefficient                =         =  1 0 0 V V T V T V V T V V dT p p T T ln , ln( / )   assuming constant or