A glass vessel is filled with water' to the rim and a lid is fixed to it tightly. Then it is left inside a freezer for hours. What is expected to happen ?

When a glass vessel is filled to the rim and tightly sealed, the water inside undergoes a phase change from liquid to solid as it cools below 0°C. Unlike most substances, water exhibits an anomalous expansion upon freezing, increasing its volume by approximately 9%. This expansion occurs because water molecules arrange themselves into a crystalline lattice structure that occupies more space than the liquid state. In a rigid, sealed glass container, there is no room for this increased volume. As the ice forms, it exerts significant crystallization pressure against the vessel's walls [1]. Since glass is a brittle material with limited tensile strength, the internal pressure generated by the expanding ice eventually exceeds the strength of the glass, causing the vessel to fracture or burst.

Sources

1. [1] https://www.nature.com/articles/s41598-025-86117-5