Paabo Maya, Bates Roger G
Institute for Materials Research, National Bureau of Standards, Washington, D.C. 20234.
J Res Natl Bur Stand A Phys Chem. 1970 Sep-Oct;74A(5):667-671. doi: 10.6028/jres.074A.055.
The first dissociation constant of piperazinium ion has been determined by the emf method in five methanol-water solvents (10 to 70 wt % MeOH) at 25 °C and in three solvents (10, 20, and 50 wt % MeOH) from 10 to 40 °C. From the variation of the dissociation constant with temperature, the changes of enthalpy, entropy, and heat capacity were derived and compared with similar data for piperazinium ion in water. The variation of , Δ°, and have been used to interpret the effect of the double positive charge on the solute-solvent interactions as compared to the effect exhibited by a single positive or a negative charge.
在25℃下，采用电动势法在五种甲醇 - 水混合溶剂（甲醇质量分数为10%至70%）中测定了哌嗪离子的一级解离常数；在10℃至40℃范围内，还在三种溶剂（甲醇质量分数为10%、20%和50%）中进行了测定。根据解离常数随温度的变化，推导出了焓、熵和热容的变化，并与哌嗪离子在水中的类似数据进行了比较。与单正电荷或单负电荷所表现出的效应相比，通过研究、Δ°和的变化来解释双正电荷对溶质 - 溶剂相互作用的影响。
