Entropy

Spontaneity is favored by a(n) _____ in energy of the system, and a(n) _____ in entropy of the system.

• increase; decrease

• increase; increase

• decrease; increase

• decrease; decrease

Predict ΔS for: 2NH₃(g) → N₂(g) + 3H₂(g)

• no change

• decrease

• impossible to predict

• increase

If the temperature of a system decreases, what will happen to entropy?

• increase

• decrease

• no change

• impossible to predict

Predict ΔS for: CO₂(g) + H₂(g) → CO(g) + H₂O(g)

• About 0

• impossible to predict

• negative

• positive

____ describes the state of order in a system.

• Spontaneous reaction

• 1st law of thermodynamics

• 3rd law of thermodynamics

• Entropy

ΔS universe = ΔS system + ΔS surroundings > 0 describes which thermodynamic law?

• 1st

• 2nd

• 3rd

• 4th

Predict ΔS for: O₂(g)(298K, 650 torr) → O₂(g)(298K, 700 torr)

• decrease

• no change

• increase

• impossible to predict

Which thermodynamic law says that energy cannot be created nor destroyed?

• 4th

• 1st

• 2nd

• 3rd

Which is always true for an endothermic reaction?

• q_sys > 0, ΔS_surr > 0

• q_sys < 0, ΔS_surr > 0

• q_sys > 0, ΔS_surr < 0

• q_sys < 0, ΔS_surr < 0

Entropy will _____ if the disorder of the phase decreases.

• impossible to predict

• increase

• not change

• decrease