Research Article
Potentiometric and Thermodynamic Studies of Some Schiff-Base Derivatives of 4-Aminoantipyrine and Their Metal Complexes
Table 6
Thermodynamic functions for ML and ML
2 complexes of ligand (L
2) in 10% (by volume) ethanol-water mixture and 0.1 mol
dm
−3 KCl.
| | /K | Gibbs energy/kJmol−1 | Enthalpy/kJmol−1 | Entropy/Jmol−1K−1 | | | | | | |
| | 298 | 41.82 | 38.46 | | | 243.82 | 229.45 | Mn2+ | 308 | 44.23 | 40.69 | 30.83 | 29.92 | 243.72 | 229.25 | | 318 | 46.70 | 43.05 | | | 243.82 | 229.45 |
| | 298 | 43.02 | 39.09 | | | 253.93 | 237.64 | Co2+ | 308 | 45.53 | 41.39 | 32.65 | 31.73 | 253.82 | 237.44 | | 318 | 48.01 | 43.83 | | | 253.93 | 237.65 |
| | 298 | 43.54 | 39.48 | | | 252.58 | 239.05 | Ni2+ | 308 | 45.99 | 41.87 | 31.73 | 31.75 | 252.38 | 239.04 | | 318 | 48.59 | 44.27 | | | 252.58 | 239.05 |
| | 298 | 44.39 | 40.34 | | | 264.61 | 248.00 | Cu2+ | 308 | 47.48 | 42.81 | 34.46 | 33.56 | 264.50 | 247.99 | | 318 | 49.68
| 45.30 | | | 264.62 | 248.05 |
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