Final answer:
The transition from the liquid state to the gaseous state is characterized by the heat of vaporization, which is the energy required for a substance's molecules to overcome intermolecular forces and enter the gaseous phase. The correct answer is an option D
Step-by-step explanation:
The transition between the liquid state and the gaseous state of a pure substance is characterized by the heat of vaporization. Option D) Vaporization is the correct choice for this question. The process of vaporization involves the absorption of energy from the environment, enabling molecules in a liquid to overcome intermolecular forces and transition into the gaseous state. This energy change, often described as the heat of vaporization (AHvap), is typically higher than the heat of fusion because a greater amount of energy is required to completely overcome intermolecular attractions.
Summarizing, when a liquid becomes a gas, the process is called vaporization (or evaporation when occurring below the boiling point), and the reverse process is known as condensation. The amount of energy needed for vaporization for each substance is characteristic and is referred to as the substance's enthalpy of vaporization.