“…Nevertheless, CaCl 2 has been used as an isopiestic standard at elevated temperatures at high concentrations mainly because of its convenience in comparison with H 2 SO 4 . For example, the model of Ananthaswamy and Atkinson [5] has been used by Grjotheim and co-workers [22][23][24][25][26][27] in a series of investigations of salt mixtures at 373 K, where calcium chloride solutions with molalities approaching 9 mol AE kg À1 were used as the reference standard.…”