Question

E. An endothermic reaction occurs in an adiabatic reactor. No work is done. What do you expect the temperature of the reactor to be after the reaction, relative to the temperature before the reaction occurred? Circle and explain your answer to receive full credit. (4 pts) a. Greater after the reaction. b. Less after the reaction. c. The temperature is the same before and after reaction. d. Not enough information to tell.

Answer 1

6) As this is an adiabatic oceacton, amountal heat input = heat output= 49 = 0, $=0 Being an endothermic reaction, SH = tve. Let initial temporatese be Ti and final temperateveebe Tz Giren, no celork is done, :AW=0. Accoring to Ist lawo of thermodynamics, 40 = 8 +AW - AU=0+0 => [AU = 0 cie know, change internal eno for any n mole of substance, AU=nG (T2-T.) Ca = specific heat at constant valeme AU = 0, hore → O-na (T2-T) -> (T2-T) = 0 [na to] T2 = Ti Also given 4H=tre. , 4H-change in enthalpy Now we know, energy AH = 4UH PAV and it is also given AW=0, . >0 at constant poressore weeknew work =) -PAV=0 done can be AH = 40 + Play Pupæsentedas -PAV -> 4H=0 [: previously formeed 40=0] - neo (ToT) = 0 Cp = the specific heat - (Ta-T)=0 na zo] => 1T2=T Thus cul see that there is no change in reactor temperature after the reaction , relative to the temperature before the reaction accured, as all have proceed earlier that TET, The option ① will be correct choice. The temperature is same before and after reaction