What is defined as a system in thermodynamics?

• Only the air molecules in a room

• The entire universe

• A group of molecules that are of interest

• The boundary around a coffee cup

According to the first law of thermodynamics, what happens to the energy lost by a system?

• It is created

• It is destroyed

• It is gained by the surroundings

• It disappears

Why doesn't the temperature of the surroundings significantly increase when a hot coffee cools down?

• The surroundings have fewer molecules

• The energy is destroyed

• The energy is evenly distributed among many molecules

• The coffee absorbs the energy back

What does the second law of thermodynamics state?

• Temperature always increases

• Energy can be destroyed

• Entropy cannot decrease spontaneously

• Energy can be created

What is entropy a measure of?

• The speed of molecules

• The concentration of energy

• The temperature of a system

• How much energy has spread out

Why can't energy from the surroundings spontaneously enter a room temperature coffee to heat it up?

• It violates the second law of thermodynamics

• It violates the first law of thermodynamics

• The coffee absorbs all the energy

• The surroundings have no energy

What happens to the entropy of a system when energy spreads out?

• It decreases

• It stays the same

• It increases

• It fluctuates

Why does heat always flow from a hot body to a cold body spontaneously?

• Because of the zeroth law of thermodynamics

• Because of the first law of thermodynamics

• Because of the second law of thermodynamics

• Because of the third law of thermodynamics

How does a refrigerator manage to transfer heat from a cold region to a warmer region?

• By using electrical energy

• By violating the second law of thermodynamics

• By spontaneous energy transfer

• By creating energy

What happens to the entropy of the total system when a refrigerator is used?

• It fluctuates

• It increases

• It decreases

• It stays the same