Partial molal heat capacity of aqueous ferrous chloride from measurements of integral heats of dilution

Heats of dilution of concentrated aqueous solutions (4.43 moles-kg^–1) of FeCl₂ were measured at 15, 25, and 35°C. The heat capacities of these concentrated solutions were also measured at the same temperatures. From these data the partial molal heat capacity, C _p2 ⁰ (FeCl₂, aq, 298.15°K)=–2.56±30 J–°K^–1–mole^–1, was calculated. The partial molal heat capacity of Fe²⁺(aq), –2±30 J-°K^–1-mole^–1, was correlated with the correspondence principle equations of Criss and Cobble.