Abstract
Previously, the author found that the traditional Clapeyron–Clausius equation fails to describe the phase transitions in substances with negative thermal expansion. A modified Clapeyron–Clausius equation was therefore proposed, which described these transitions very well. However, this modified equation failed to describe the melting of ice. It is shown here that the modified Clapeyron–Clausius equation describes the melting of ice successfully if the compressibility of water and ice is considered.