Thermochemistry and thermodynamics of solution of styphnic acid in DMF at 298.15 K

The enthalpies of solution and the thermodynamics of styphnic acid 2,4,6-trinitroresorcinol (TNR) the solution solved in DMF were studied. The enthalpies of TNR solution with different concentrations were measured by a SETARAM C80 II calorimeter at 298.15 K and the empirical formula for enthalpies of TNR solution is calculated by polynomial simulation on the computer. The results show that the formula is Δ_soliH = -14.392 - 988.66 + 34.9926^1/2. The standard molar enthalpy of solution is determined to be Δ_solH_m^θ = -14.392 kJ · mol^-1. The relative apparent molar enthalpies of solution (ΦL_I), the relative partial molar enthalpies (L_i), enthalpies of dilution (Δ_dilH_1,2) are also stretched respectively. The thermodynamics of TNR solution was studied by analyzing heat-flux to time curves, the rate constant of reaction and the reaction order were determined to be 1.632 × 10^-3 s^-1 and 0.6158, respectively.