Thermal dehydration and decomposition of M[M(C2O4)2]·xH2O (x=3 forM=Sr(II) andx=6 forM=Hg(II)) |
| |
| Authors: | N. Deb S. D. Baruah N. N. Dass |
| |
| Affiliation: | (1) Department of Chemistry, J. B. College, Jorhat, 785 001 Assam, India;(2) Regional Research Laboratory, Jorhat, 785 006 Assam, India;(3) Department of Chemistry, Dibrugarh University, Dibrugarh, 786 004 Assam, India;(4) Present address: Department of Chemistry, North Eastern Regional Institute of Science & Technology, Nirjuli, 791109 Arunachal Pradesh, India |
| |
| Abstract: | Strontium(II) bis (oxalato) strontium(II) trihydrate, Sr[Sr(C2O4)2]·3H2O and mercury(II) bis (oxalato) mercurate(II) hexahydrate, Hg[Hg(C2O4)2]·6H2O have been synthesized and characterized by elemental analysis, reflectance and IR spectral studies. Thermal decomposition studies (TG, DTG and DTA) in air showed SrCO3 was formed at ca. 500°C through the formation of transient intermediate of a mixture of SrCO3 and SrC2O4 around 455°C. Sharp phase transition from γ-SrCO3 to β-SrCO3 indicated by a distinct endothermic peak at 900°C in DTA. Mercury(II) bis (oxalato) mercurate(II) hexahydrate showed an inclined slope followed by surprisingly steep slope in TG at 178°C and finally 98.66% of weight loss at 300°C. The activation energies (E *) of the dehydration and decomposition steps have been calculated by Freeman and Carroll and Flynn and Wall's method and compared with the values found by DSC in nitrogen. A tentative reaction mechanism for the thermal decomposition of Sr[Sr(C2O4)2]·3H2O has been proposed. |
| |
| Keywords: | activation energy complexes kinetics oxalato complexes thermal decomposition |
| 本文献已被 SpringerLink 等数据库收录！ |
|
