Entropy Concepts in Thermodynamics

What is the entropy of a pure crystalline substance at absolute zero according to the third law of thermodynamics?

• Zero

• Infinite

• One

• Negative

How does the entropy of a substance change as the temperature increases?

• It becomes zero

• It increases

• It remains constant

• It decreases

What is the standard molar entropy of graphite at 25 degrees Celsius?

• 5.7 joules per kelvin mole

• 0 joules per kelvin mole

• 69.9 joules per kelvin mole

• 186.3 joules per kelvin mole

Which state of matter generally has the highest standard molar entropy?

• Solids

• Liquids

• Gases

• Plasmas

Why do gases generally have higher entropy than solids?

• Gases have fewer particles

• Gases have more microstates due to increased freedom of movement

• Gases are denser

• Gases have stronger intermolecular forces

What is the standard molar entropy of methane gas?

• 5.7 joules per kelvin mole

• 229.6 joules per kelvin mole

• 186.3 joules per kelvin mole

• 69.9 joules per kelvin mole

In the decomposition of calcium carbonate, what is the sign of the standard change in entropy?

• Positive

• Negative

• Zero

• Undefined

What is the standard change in entropy for the decomposition of one mole of calcium carbonate?

• 92.9 joules per kelvin

• 160.5 joules per kelvin

• 39.8 joules per kelvin

• 213.6 joules per kelvin

How does the number of moles of gas on the product side affect the entropy change in a reaction?

• It makes the entropy zero

• It increases the entropy

• It has no effect

• It decreases the entropy

If the decomposition of two moles of calcium carbonate is considered, how would the change in entropy compare to one mole?

• It would be double

• It would be zero

• It would be the same

• It would be half