What change occurs when an ice cube melts?

When an ice cube melts, a phase change occurs from solid to liquid. This process happens when the temperature of the ice rises to its melting point, causing the ice molecules to gain energy and break the bonds that hold them in a rigid structure. As a result, the solid ice transforms into liquid water.

This concept illustrates the principles of phase changes in materials, where energy transfer in the form of heat facilitates the transition between different states of matter. The melting of ice is a clear example of this principle in action, reinforcing the understanding of thermodynamics in HVAC systems, where temperature and phase changes are integral to the operation of refrigeration cycles.