Preparation and Thermal Chemical Property of Complexes of Zinc Nitrate with Trytophan

✍ Scribed by Chen San-Ping; Gao Sheng-Li; Yang Xu-Wu; Shi Qi-Zhen

• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 368 KB
• Volume: 21
• Category: Article
• ISSN: 0256-7660
• DOI: 10.1002/cjoc.20030210612

✦ Synopsis

The solubility property of Zn(N03)2-Try-R20 system at 25 T in whole concentration range has been investigated by the semimicro phase equilibrium method. The corresponding phase dia- grams and refractive index diagrams were constructed. Under the guidance of the phase equilibrium results, the incongruently soluble compounds of Zn (Try ) ( NO3 )2 2H20 ( F ) and Zn-(Try)2(N03)2-H20 ( G ) , which have not been reported previously, were synthesized and characterized by IR, XRD, TG-DTG, as well as chemical and elemental analyses. The constant-volume combustion energies of the compounds, 4 E , determined by a precision rotating bomb calorimeter at 298.15 K , were(-13518.98*4.99) J -g -l a n d (-17690.85i4.88) J . g-', respectively. The standard enthalpies of combustion for these compounds, L H , were calculated to be ( -5802.36 i 2.14) W-rnol-' and ( -10891.59 i 3.01) kJ*mol-' when the standard enthalpies of formation, ArH@ were ( -1161.18 i 2.61) kJ-mol-' and ( -1829.71 i 4.20) kJ*mol-'. The enthalpies of solution in condition of simulating human gastric juice (37 T , pH = 1 , the solution of hydrochloric acid), which were also measured by a microcalorimeter, were ( 14.55 f 0.04) kJ.mol-' and (10.58i0.06) kJ-mol-', respectively. Keywords tion, standard enthalpy of formation ternary system, zinc nitrate, eytophan , characteriza-