Answer:
the number of possible configurations of the locations and energies of the atoms or molecules that comprise a system
Step-by-step explanation:
Ludwig Boltzmann was the first to suggest that the concept of entropy could be calculated by examining the positions and energies of molecules. This was developed into an equation, known as the Boltzmann equation, which relates entropy to the number of microstates (W):
S = k ln W
where k is the Boltzmann constant (1.38 x 10-23 J/K), and W is the number of microstates.
Microstates was used to imply the number of different possible arrangements of molecular position and kinetic energy at a particular thermodynamic state. Therefore any process that gives an increase in the number of microstates therefore increases the entropy. Hence the answer.