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实验中配制一系列不同pH值的吡啶和2，6-二甲基吡啶的水溶液，用80MHz核磁共振谱仪测定每个pH点的核磁共振图谱．根据平衡常数与pH值及离子浓度的关系，可以计算出pKα的值．改变体系的实验温度，可以得到热力学参数△H、△S和△G的值．研究结果表明，核磁共振的方法是可靠的，它比传统的pH滴定方法测定pKα值的方法简单得多．
In the experiment, a series of aqueous solutions of pyridine and 2,6-lutidine with different pH values were prepared, and the nuclear magnetic resonance spectra of each pH point were measured with an 80 MHz nuclear magnetic resonance spectrometer. The value of pKα can be calculated from the relationship between the equilibrium constant and pH and ion concentration. By changing the experimental temperature of the system, the thermodynamic parameters ΔH, ΔS and ΔG can be obtained. The results show that the NMR method is reliable and is much simpler than the traditional pH titration method for pKa.