Melting ice is which type of change?

• A. Melting ice is a physical change.
• B. Melting ice is a chemical change.
• C. It is neither; it's a phase change not involving energy.
• D. It depends on pressure.

Answer: (A)

Melting ice is a physical change. When ice melts, it stays as the same substance, H2O, just in a different state. The molecules don’t react to form new substances; they simply move from a rigid solid arrangement to a more fluid liquid, and energy is absorbed to overcome the forces holding the solid together. Because the chemical identity doesn’t change, melting is reversible by freezing back into ice.

This isn’t a chemical change, where new substances with different properties would be formed. It also isn’t “not involving energy”—melting requires energy input (latent heat of fusion). Pressure can affect the melting point, but that doesn’t change the fact that the process is a physical phase change with the same composition.