The behavior of H₂O and CO₂ in high-temperature lead borate solution calorimetry of volatile-bearing phases

High-temperature oxide melt solution calorimetry with molten 2PbO.B₂O₃ as a solvent can be used for determining enthalpies of formation of carbonates and hydrous silicates. Under conditions of gas flow at 1-2 cm³/s, all H₂O and CO₂ is expelled from the solvent, leading to a reproducible final thermodynamic state. Both analytical data and a number of thermodynamics cycles show that, under these conditions, the volatiles neither dissolve in nor interact energetically with the melt. -Authors