以下是兩題有關熱力學的題目 可以大概告訴我算法就好 但一定要有答案 若能回答全部者將奉上200p~ 1.Consider 1 mole of N2 gas undergoing the change from an inatial state(P1,V1 ,T1) to a final state of (P2,V2,T2), in which P,V and T represent pressure, volume, and temperature, respectively. (a) Assuming that the gas behaves ideally, and we know that P1=1.50atm, T1= 298K, P2=0.5atm, and T2=200K, calculate V1 and V2. (5%) (b) There are always many paths one could take to change the gas from one state to another. Consider the special path as followings: a constant volume path of V1 from the initial (P1,V1) state to an intermediate state (P2,V2), and then taking a constant pressure path from (P2,V1) to the final (P2,V2) state. With the conditions listed in part(a), calculate the total work done and the total heat transferred by the gas for this specific path. (5%) (c) Calculate the internal energy change and the enthalpy change for the complete process form state 1 to state 2. (5%) Additional information: (i) The constant-volume and constant-pressure molar heat capacities of N2(g) are 20.8 and 29.1 Joule/(K mol), respectively. (ii) The gas constant R = 0.0821 L atm K^-1 mol^-1 = 8.31 J K^-1 mol^-1 (iii) 1 L atm = 101.3 J 2. Consider the combustion reaction of the normal butane gas: C4H10(g) + 13/2 O2(g) →4 CO2(g) + 5 H2O(g) With the help of the related thermodynamic data as listed below, aswer the following questions: (a) At 1.00 atm, calculate △H of this reaction at 298K and 1000K, respectively. (5%) (b) Calculate the theoretical maximum temperature that could be reached by igniting a mixture of butane and the air (O2/N2 mole ratio 1/4) under 1 atm constant pressure (i.e. the operation condition of a butane stove used in camping or in a picnic). The initial system temperature is assumed to be 298K. (5%) (c) Instead of the air, if pure oxygen was used in (b), what would be the theoretical maximum temperature one could reach in the butane stove? (5%) Related thermodynamic data: theoretical maximum temperature one could reach in the butane stove? (5%) Related thermodynamic data: (i) Molar heat capacities at constant pressure (J/mol): O2(g)=29.5 N2(g)=29.1 H2O(l)=75.2 H2O(g)=24.8 CO2(g)=37.3 C4H10(g)=97.5 (ii) Standard enthalpies of formation (KJ/mol) at 298K: CO2(g)=-394 C4H10(g)=-125 H2O(l)=-286 H2O(g)=-242 --

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