Which of the following processes are spontaneous andwhich are nonspontaneous: (a) the ripening of a banana,(b) dissolution of sugar in a cup of hot coffee, (c) the reactionof nitrogen atoms to form N2 molecules at 25 °C and1 atm, (d) lightning, (e) formation of CH4 and O2 moleculesfrom CO2 and H2O at room temperature and 1 atm ofpressure?

(a) Does the entropy of the surroundings increase for spontaneousprocesses? (b) In a particular spontaneous processthe entropy of the system decreases. What can you concludeabout the sign and magnitude of ΔSsurr? (c) Duringa certain reversible process, the surroundings undergo anentropy change, ΔSsurr = -78 J/K. What is the entropychange of the system for this process?

2 NH3 (g) + 2 O2 (g) → N20 (g) + 3 H2O (g) Is this reaction spontaneous only at low temperatures, only at high temperatures, at all temperatures? AH°r, kJ/mol s°, J/mol·K NH3(g) -46.1 192.5 0:(g) 205.0 N 20 (g) 82.1 219.9 H2O(g) |-241.8 188.7 AH°i, kJ/mol s°, J/mol·K What is the lowest temperature at which the following reaction is spontaneous? H2O (g) + C (s) → H2 (g) + CO (g) Co(g) H2(g) C (s) -110.5 | 197.7 130.6 5.7 H2O(g) |-241.8 188.7

For the following reaction (the detonation of nitroglycerin), is it spontaneous under standard conditions and how can you tell? 4 C4H5N3O9(l) (arrow >) 12 CO2(g) + 10 H2O(g) + 6 N2(g) + O2(g)    ΔH = -5678 kJ