Question 1
For a spontaneous process
◦ both the energy and the entropy of the system and surroundings decrease.
◦ energy and entropy are conserved.
◦ energy is conserved and the entropy of the system and surroundings increases.
◦ the energy of the system and the surroundings decreases and the entropy of the system and surroundings increases.
Question 2
For the process
CaCO3(calcite) → CaCO3(aragonite) ΔH° = -0.21 kJ, ΔS° = -4.2 J/K
Assuming that the surroundings can be considered a large heat reservoir at 25°C, calculate Δ
Ssurr and Δ
Stotal for the process at 25°C and 1 atm pressure. Is the process spontaneous at 25°C and 1 atm pressure?
◦ Δ
Ssurr = -0.7 J/K, Δ
Stotal = -4.9 J/K, not spontaneous
◦ Δ
Ssurr = 0.7 J/K, Δ
Stotal = -3.5 J/K, not spontaneous
◦ Δ
Ssurr = -0.7 J/K, Δ
Stotal = -4.9 J/K, spontaneous
◦ Δ
Ssurr = 4.2 J/K, Δ
total = 0, not spontaneous
