Thermodynamic pathway terminology: When a system moves from one equilibrium state to another, the sequence of intermediate states followed is called a ________.

Introduction / Context:
Thermodynamics distinguishes between states (points) and the path taken between states. Correctly naming the path concept is essential for applying path-dependent quantities like heat and work versus state functions like internal energy and entropy.

Given Data / Assumptions:

• Two distinct equilibrium states are defined for a closed or open system.
• Quasi-equilibrium description allows a continuous path of states.
• Heat and work depend on the path, not only on end states.

Concept / Approach:

The term for the path of successive equilibrium states is a thermodynamic process. A thermodynamic cycle is a special process that returns to the initial state. Laws of thermodynamics govern relations between properties and transfers but are not the path itself.

Step-by-Step Solution:

Verification / Alternative check:

On P–v or T–s diagrams, the curve between two points is the process path; enclosing a loop forms a cycle.

Why Other Options Are Wrong:

Thermodynamic law: a principle (e.g., First/Second law), not a path.Thermodynamic cycle: requires returning to the starting state.State function: a property defined by state, not a path.

Common Pitfalls:

Confusing a process with a law or with a specific device model; a process is generic and device-independent.

Final Answer:

thermodynamic process