10. The species in the reaction, 2 KNO3 (s) +2 C(s) K2C03 (s) + N2(g).3/2 002(g)
ID: 588704 • Letter: 1
Question
10. The species in the reaction, 2 KNO3 (s) +2 C(s) K2C03 (s) + N2(g).3/2 002(g) have the values for standard enthalpies of formation at 25 ·C: KNO3(s), AH 492.7 kJ mol co2(g). Aff=-3940 kJ mor! K2Cos(o), AH-1146 kJ mol Make the assumption that, since the physical states do not change, the values of ar' and , atm range, and use this conditions may apply -S are constant throughout a broad temperature information to determine which of the following a. It i insuffici presented. s impossible to make any judgment about spontaneity because ent information can be gleaned from the data and equations b. The reaction is non-spontaneous at low temperatures but spontaneous at high temperatures. c. The reaction is spontaneous at low temperatures but non-spontaneous at high temperatures. d. The reaction is non-spontaneous at all temperatures. e. The reaction is spontaneous at all temperatures. Answer: 11. For a certain chemical reaction, AH is> 0 and As is s 0.This meansExplanation / Answer
delta Hrxn = delta H of products - delta H of reactants
delta Hrxn = (delta Hf of K2CO3 + delta Hf of N2 + 3/2 delta Hf of CO2 ) - (2*delta Hf of KNO3 + 2*delta Hf of C)
delta Hf of pure elements is zero
delta Hrxn = (-1146 + 0 + 3/2*-394) - ( 2*-492.7 + 2*0)
delta Hrxn = -751.6 KJ
delta S is positive because products are gaseous in state whereas reactants are in solid state
Gaseous have more randomness than solids
delta S > 0
delta G = delta H - T*delta S
delta G is negative then the reaction is spontaneous
the reaction is spontaneous at all temeperatures (as delta H is -ve and delta S is +ve)
Answer is e
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.