The free proton concentration scale for seawater pH
The free proton concentration scale for seawater pH
复制标题
海水 pH 值的自由质子浓度标度
DOI：
10.1016/j.marchem.2012.11.003
复制
发表时间：
2013
期刊：
影响因子：
3
通讯作者：
F. Millero
中科院分区：
文献类型：
--
作者：
J. Waters;F. Millero
由于在海水中使用多个pH值标度，与海洋环境pH值有关的研究不必要地复杂，并且容易不准确。最好采用一个标准标度，我们建议使用游离质子pH标度。为了确保自由质子标度的准确性，并与海水中的主要pH测量结果保持一致，我们使用Pitzer离子相互作用模型重新评估HSO 4 −和H2CO3的自由标度pH和化学计量解离常数。Pitzer模型在盐度为5至45、温度为0至45°C的条件下，使用测得的人工海水中HCl的平均活度系数进行验证。所得的标准电位和化学计量解离常数进行比较，以前的估计。经验证的模型结果用于评估等摩尔（m=0.04molkg−1）胺缓冲液在游离质子浓度标度上的pH值的更准确值，该值可用于校准天然沃茨中的游离标度pH测量值。
Due to the use of multiple pH scales in seawater, studies related to the pH of marine environments are unnecessarily complicated and prone to inaccuracy. It is desirable that a standard scale be adopted, and we suggest the free proton pH scale be used. To ensure that the free proton scale is accurate and consistent with primary pH measurements in seawater, we use the Pitzer ion-interaction model to re-evaluate the free scale pH and stoichiometric dissociation constants of HSO4−and H2CO3. The Pitzer model is validated over a salinity range of 5 to 45 and temperatures of 0 to 45°C using the measured mean activity coefficient of HCl in artificial seawater. The resulting standard potential and stoichiometric dissociation constants are compared to previous estimates. The validated model results are used to evaluate more accurate values for the pH of equi-molal (m=0.04molkg−1) amine buffers on the free proton concentration scale, which can be used to calibrate free scale pH measurements in natural waters.