在可变温度 (10-85摄氏度) 下,的水解
PierLuigi Zanonato1, Plinio Di Bernardo, Arturo Bismondo
1Dipartimento di Chimica Inorganica Metallorganica ed Analitica, Università di Padova, via Loredan 4, 35131, Padova, Italy.
Journal of the American Chemical Society
|April 29, 2004
概括
(VI) 的水解随着温度的增加而显著增加,影响了水解常数和度. 这项研究量化了这些依赖于温度的物种变化.
科学领域:
- 无机化学 无机化学 有机化学
- 水性地质化学 水性地质化学
- 核化学 核化学 核化学
背景情况:
- 对于了解的环境行为和核燃料再加工而言, (VI) 变种是至关重要的.
- 温度显著影响化学平衡,包括水解反应.
- 关于的温度依赖性,水解常数和热力学数据有限.
研究的目的:
- 为了研究(VI) 在化物介质中的水解的温度依赖性.
- 在温度范围 (10-85 °C) 中确定水解常量 (*β) 和水解度 (Delta H) 和水解恒量 (*β) 和水解度 (Delta H).
- 评估水解的热容量,并验证温度效应的预测模型.
主要方法:
- 用电位计定位来确定水解常数.
- 热量计用于测量水解的度.
- 紫外线/Vis吸收光谱和时间分辨率激光诱导光谱提供了互补的物种化数据.
主要成果:
- 水解常数 (*β1,1), *β2,2), *β5,3) 随着温度的增加增加增加了2-5个数量级.
- 水解的度 (Delta H2,2,Delta H5,3) 显示了温度依赖的变化,变得或多或少的内热.
- 水解的计算热容量是Delta C (p (2,2)) = (152 ± 43) J K−1 mol−1和Delta C (p (5,3)) = -229 ± 34) J K−1 mol−1.
结论:
- 升高的温度显著增强了 (VI) 的水解,改变了其水性物种.
- 热力学参数 (热量,热容量) 对于在不同热条件下精确建模的行为至关重要.
- 该研究为预测温度对水解的影响提供了有价值的数据,并验证了近似方法.
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