Leaving Certificate Engineering Practice Exam 2026 – Complete Study Guide

The correct answer is that the temperature of the metal decreases until solidification occurs. This reflects the process of cooling a pure metal, where the temperature gradually drops as the metal loses heat to its surroundings.

Initially, when a molten metal begins to cool, its temperature decreases continuously. As it approaches its freezing point, the cooling rate slows down significantly. Eventually, once the metal reaches its solidification temperature, it will solidify into a solid state. During this phase change, any additional heat loss does not result in a decrease in temperature; instead, it contributes to the process of solidification, where the metal transitions from a liquid to a solid.

This phenomenon aligns with the principles of thermodynamics and phase change, highlighting that materials maintain a constant temperature during phase transitions. It also illustrates the distinction between the liquid phase cooling and the solidification process, making it clear why the other options do not accurately represent what happens during the cooling of a pure metal.