The best match for the definition "a process that is capable of proceeding under a specified set of conditions in a given direction, without needing to be driven by an outside source of energy" is:
c. spontaneous process
Here's why:
- Othermochemical equation: This describes a chemical reaction with heat flow in a specific direction, but it doesn't necessarily imply spontaneity. Some endothermic reactions can be spontaneous under certain conditions.
- Extensive property: This refers to a property that depends on the amount of matter in a system, not its specific composition or form. It doesn't necessarily relate to the direction or energy requirements of a process.
- Intensive property: This refers to a property that does not depend on the amount of matter in a system, such as density or temperature. It still doesn't capture the essential characteristic of a spontaneous process.
- Spontaneous process: This precisely matches the definition. It describes a process that can occur naturally and progress in a particular direction without needing external energy input. Examples include ice melting at room temperature, water flowing downhill, and chemical reactions that release energy.
Therefore, c. spontaneous process is the most accurate option based on the provided definition.