Explanation:
- Entropy is a thermodynamic property that measures the degree of disorder or randomness in a system.
- It is denoted by the symbol S and is defined as the amount of energy in a system that is no longer available to do work.
- At absolute zero temperature (0 K), all molecular motion comes to a complete stop, and the system reaches its lowest possible energy state.
- Since entropy is related to the degree of disorder or randomness, at 0 K, the system is in its most ordered state with no randomness or disorder.
- In other words, there is only one possible microstate or configuration that the system can have at 0 K, which is the most ordered state.
- Therefore, the entropy of a system at 0 K is zero since there is no randomness or disorder present.
- This is consistent with the third law of thermodynamics, which states that the entropy of a perfect crystal at absolute zero temperature is zero.
- The third law of thermodynamics also implies that it is not possible to reach absolute zero temperature in a finite number of steps.
- However, in theory, if absolute zero temperature could be reached, the entropy of the system would be zero.
- Therefore, the correct answer is option 'B', the value of entropy at 0 K is zero.