3.7 - Entropy

What does entropy measure in a system?

• The amount of disorder

• The degree of freedom

• The temperature

• The pressure

Which physical state has the highest entropy?

• Solid

• Liquid

• Gas

• Plasma

What happens to entropy when a substance changes state from solid to liquid?

• Entropy increases

• Entropy decreases

• Entropy remains the same

• Entropy cannot be determined

What factor can increase entropy in a system?

• Mixing and dissolving

• Decreasing temperature

• Decreasing pressure

• Increasing order

What is the standard entropy of a substance?

• The entropy of one mole in a given physical state under standard conditions

• The entropy of one gram in a given physical state under standard conditions

• The entropy of one litre in a given physical state under standard conditions

• The entropy of one atom in a given physical state under standard conditions

According to the second law of thermodynamics, entropy will tend to ________ in an isolated system.

• Decrease

• Remain constant

• Increase

• Fluctuate

What factor determines the feasibility of a reaction?

• Change in entropy

• Change in enthalpy

• Both change in entropy and change in enthalpy

• None of the above

What is the entropy change when a liquid boils?

• Entropy increases

• Entropy decreases

• Entropy remains the same

• Entropy cannot be determined

Which represents a -ΔS?

• ice melting

• salt dissolving

• water heating up

• none of these

Which of these have a DECREASE in entropy?

• CaCO₃(s) → CaO(s) + CO₂(g)

• 2NO₂(g) → N₂O₄(g)

• 2NH₃(g) → 3H₂(g) + N₂(g)

• C₆H₆(l) → C₆H₆(g)