Mastery: Enthalpy, Entropy & Spontaneity

Which phase change results in an increase in disorder?

• I₂(g) → I₂(s)

• Cl₂(ℓ) → Cl₂(g)

• N₂O₄(g) → N₂O₄(ℓ)

• H₂O(ℓ) → H₂O(s)

Systems in nature tend to undergo changes that result in

• an increase in both energy and entropy

• a decrease in both energy and entropy

• an increase in energy and a decrease in entropy

• a decrease in energy and an increase in entropy

Tags

NGSS.HS-PS3-4

Systems in nature tend to change toward

• lower energy and less disorder

• lower energy and greater disorder

• higher energy and less disorder

• higher energy and greater disorder

Which phase change represents an increase in entropy?

• liquid to gas

• liquid to solid

• gas to solid

• gas to liquid

Which term represents the disorder of a system?

• entropy

• mole

• quanta

• pressure

Based on Table I, which equation represents conservation of mass and energy?

• CH₄(g) + O₂(g) + 890.4 kJ → CO₂(g) + H₂O(ℓ)

• CH₄(g) + O₂(g) → CO₂(g) + H₂O(ℓ) + 890.4 kJ

• CH₄(g) + 2O₂(g) → CO₂(g) + 2H₂O(ℓ) + 890.4 kJ

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-2

The greatest increase in entropy occurs when a 1.00-gram sample of water changes from

• solid to liquid

• solid to gas

• gas to liquid

• liquid to solid

Based on Table I, which chemical equation represents a reaction with a heat of reaction that indicates a net release of energy?

• N2(g) + O2(g) → 2NO(g)

• N2(g) + 2O2(g) → 2NO2(g)

• 2C(s) + 3H2(g) → C2H6(g)

• 2C(s) + 2H2(g) → C2H4(g)

Tags

NGSS.HS-PS1-4

Systems in nature tend to undergo changes toward

• higher energy and higher entropy

• higher energy and lower entropy

• lower energy and higher entropy

• lower energy and lower entropy

Tags

NGSS.HS-PS3-4

Systems in nature tend to undergo changes toward

• lower energy and less disorder

• lower energy and greater disorder

• higher energy and less disorder

• higher energy and greater disorder