Chapter 3.4

Question 1

What is the second law of thermodynamics

Answer 1

• objects in thermal contact and not in thermal equilibrium
• > will exchange heat energy from the higher temperature object to the lower temperature object
• > until both objects have the same temperature at thermal equilibrium

Question 2

What is entropy? Give an example referring to ice and water

Answer 2

• entropy is the measure of the spontaneous dispersal of energy at a specific temperature
• eg; energy is dispersed over a larger number of microstates in liquid water
• > therefore, liquid water has greater entropy than ice

Question 3

When does entropy increase or decrease at a given temperature

Answer 3

• when energy is distributed into a system at a given temperature
• > entropy increases
• when energy is distributed out of a system at a given temperature
• > its entropy decreases

Question 4

What does the second law of thermodynamics claim about the entropy of the universe

Answer 4

• it claims the entropy of the universe is increasing

- >energy will spontaneously spread out and entropy will increase if it is not hindered from doing so

Question 5

What is the key to a reversible reaction? Do we consider freezing and melting of water to be reversible processes?

Answer 5

• the process goes slowly
• > requiring an infinite amount of time
• > system is always in equilibrium
• > no energy is lost or dissipated
• freezing and melting of water are not considered reversible processes
• > because they need to be in specific conditions to freeze or melt

Question 6

What is the relationship between the entropy of a system and its surroundings

Answer 6

• it will never decrease

- >it will either remain at zero or increase