Question

Explain the answer

Which of the following statements about entropy is false?

		a )Entropy is a measure of molecular disorder.
		b) Entropy is a property and process path independent.
		c ) Entropy is always generated during a process, including in a Carnot cycle.
		Entropy can decrease during a process.

Answer 1

a) entropy is a measure of molecule disorder- this is true as it measure the disorderliness/randomness of the system. It measures the number of way in which energy is degraded.

b) true. Entropy is a thermodynamic quantity which depends on the end states and not on the path followed by the system. So, it is path independent or a state function.

c) true. Entropy generation depends on the irreversibility of the process. Almost all the practical proceses are irreversible in nature. For irreversible process entropy >0 and is 0 for reversible proceses. Carnot cycles has 4 stages isothermal expansion and adiabatic expansion followed by isothermal and adiabatic compression. Entropy in this process at each stage is determined as the ratio of heat absorbed and the temperature at which it is taking place.

d) false. According to second law of thermodynamics, entropy of a system remains constant or increases. So it never decreases.