Consider the following spontaneous reaction between What are the signs (+, -, or
ID: 1063093 • Letter: C
Question
Consider the following spontaneous reaction between What are the signs (+, -, or 0) of Delta H Delta S Delta G This reaction becomes nonspontaneous at lower temperatures, becomes nonspontaneous at higher temperatures, or is spontaneous at all temperatures? Ethylene oxide, C_2H_4O is used to make antifreeze. It is produced industrially by the catalyzed air oxidation of ethylene: 2C_2H_4(g) + O_2(g) rightarrow 2C_2H_4O(g) At 298 K Delta G degree, equals 68.1 kJ/mol and -13.1 kJ/mol for C_2H_4(g) and C_2H_4(g) and C_2H_4O(g) respectively. What is Delta G degree at 298 K. Is this reaction spontaneous at this temperature? At 1103 K, K_p = 0.13 for the reaction: 2SO_2(g) + O_2(g) irreversible 2SO_3(g). Determine at this temperature Delta G degree (in kJ/mol) Delta G(in kJ/mol) for a mixture consisting of 0.250-atm of SO_2, 0.150 atm of O_2 and 0.0563 atm of SO_3 The dissociation reaction is illustrated right Delta G for the initial state is positive, negative, zero Delta G at equilibrium positive, negative, zero Delta G degree at equilibrium positive, negative, zeroExplanation / Answer
6]
delta H - negative
delta S = Negative
Reaction is nonspontaneous at higher temperatures
7]
delta Grxn = delta G of products - delta G of reactants
delta Grxn = -162.4 KJ
since delta G is negative
The reaction is spontaneous at 298 K
8]
deltaa G = -RT ln Kp
Substituting all values
delta G = 18.709 KJ
Kp = pSO3^2 / pSO2^2 *pO2
Kp = 0.338
delta G = -RT lnKp = 9.944 KJ
9]
At initial
Q = 3/8
Keq = 3
Q<Keq
delta G at initial = positive
delta G at equilibrium = 0
Go at equilibrium = negative