Entropy and the Second Law of Thermodynamics

Which one of the following statements best describes a reversible process?

• All heat input into the system is converted into work during the process.
• The overall entropy of the system does not increase during the process.
• The initial and final temperatures for the process are the same.
• The entropy of the system decreases during the process.
• Statements (b) and (c) both describe a reversible process.

Tags

NGSS.HS-PS1-5

How does entropy differ from energy?

• Entropy does not obey a conservation law.
• Entropy may be spelled differently, but otherwise it is a form of energy.
• Entropy always remains constant.
• Entropy relates to the transfer of energy.
• Energy can only decrease, but entropy can only increase.

Which of the following choices exhibits the lowest degree of entropy?

• a diamond crystal
• liquid oxygen
• ammonia vapor
• water in a quiet pond
• a block of paraffin

Which one of the following statements correctly describes the term state property?

• A state property gives a complete description of the system.
• A state property describes any system property that is conserved.
• A state property indicates which microstate the system is in.
• A state property is a property that does not depend on the history of the system.
• A state property describes the amount of heat added to or removed from a system.

Which one of the following statements best describes the operation of a heat engine?

• A heat engine transfers heat from a higher temperature reservoir to a lower temperature reservoir through work performed on the system.
• A heat engine transfers heat from a lower temperature reservoir to a higher temperature reservoir through work performed on the system.
• A heat engine performs work and generates an equal amount of heat in a cyclic process.
• A heat engine decreases the entropy of the universe by generating an equal amount of heat and work.
• A heat engine uses input heat to perform work and rejects excess heat to a lower temperature reservoir.

Tags

NGSS.HS-PS3-4

Which one of the following statements concerning heat engines is false?

• A heat engine receives heat from a hot reservoir.
• A heat engine is a device that uses heat to do work.
• Heat engines generally operate near one hundred percent efficiency.
• Part of the heat input to the engine is used to do work by the working substance within the engine.
• Part of the input heat is rejected to a cold reservoir.

Tags

NGSS.HS-PS3-4

Which one of the following statements concerning an ideal engine is true?

• The entropy of the system decreases with time.
• No heat transfer occurs between the system and its surroundings.
• All system processes are reversible.
• The temperature of the system is usually constant.
• The system cannot be used to perform work.

Tags

NGSS.HS-PS3-4