Experimental Considerations:

An idealized thermometric titration curve is represented in Figure showing four regions: region 1 is the baseline that is ideally horizontal but in practice it always has finite slope because of frictional heat added through stirring, resistive heat added through the thermistor and the transfer of heat from the cell to the thermostat. If heating due to friction and resistance are constant and equal to W, the slope of region I that is represented by

dT/dt = C(Tc-Te)  +  W                                                                   ... (1)

where c = the heat leak modulus, Tc = the temperature of the cell, Te = the temperate of the environment.

In case of Region 2 slope is because of same effects as a in Region 1 and following cases; temperature change produced through the reaction, the heat of dilution of the reactants ?Hd) and the difference in temperature where among titrant and sample after the start of titration (?Tr), It is represent by

dT/dt =-C(T_c-T_e)+W+(-?H/C'_p)(dn_p/dt)+(?HD/C''_p)+?T_rk                ...(2)

where k is a constant and np is the fraction product. In Region 3, equivalence point has been passed and the slope of the curve is described by

dT/dt =C(T_c-T_e)+W+?H_d/C'_p+?T_r                                ...(3)

After this no more titrant in added and the slope in Region 4 obeys Eq. (1). In real titration, therefore, a rounding is observed at the equivalence point and this case is dealt separately.

The Eq. 1-3 can be combined to obtain the heat of reaction ?H and if the production of product (n_p) is equilibrium, controlled, equilibrium constant K of the reaction can be calculated as-

-?G = RT In K = - ?H + T?S                                              .... (4)