Abstract: Water is one of the most common substances in nature and the foundation for the survival of Earth’s carbon-based life forms. Although water molecules and their related physical and chemical effects have been extensively studied, many peculiar phenomena caused by water still cannot be scientifically explained. The Mpemba effect is one typical example. In 1969, Mpemba and Dr. Denis Osborne reported in the British journal “Physics Teacher” that, under the same mass and cooling conditions, water with a higher initial temperature freezes before water with a lower initial temperature. This phenomenon, which seems to defy thermodynamic common sense, has received long-term and widespread attentions. However, due to the complexity of this phenomenon, the academic community has not been able to provide a scientifically rigorous explanation so far. Given the widespread impact of the Mpemba effect on daily production and life, this article summarizes the possible causes and influencing factors based on reported research results, aiming to present a systematic progress in research and enhance readers’ understanding of the Mpemba effect.

Key words: water, Mpemba effect, hydrogen bond, super-cold, ice