Question

Question Not yet answered A reaction at 4.21 atm produces 24.6 L of a gas and evolves 69.7 kJ of heat (exothermic). Calculate the change in internal energy of the system (in kJ). Marked out of 1.00 Answer: Flag question Question 8 Not yet answered Marked out of 1.00 1.495 g of an unknown hydrocarbon (108.1 g/mol) burns in bomb calorimeter in excess oxygen. The heat capacity of the calorimeter,cy, = 5.294 kJ/°C and AT -6.744 °C. Find AE for this hydrocarbon in kJ/mol. Hint given in feedback. P Flag question Answer: Question 9 Not yet answered Using the technique of the previous problem AE was found to be -2,000.00 kJ/mol of an unknown liquid hydrocarbon at 298 K. In another experiment it was determined that for each mole of hydrocarbon, 6 moles of oxygen gas are consumed and 7 moles of CO2 gas and 7 moles of H2O liquid are produced. Find AH per mole of this hydrocarbon (in kJ) at 298 K. Marked out of 1.00 P Flag question Hint given in feedback. Not used to answer question: This question is a bit awkward and unrealistic for molar amounts, but allows for random numbers. An example of a possible reaction is: CHA(OH)2(0) +2.502(g) +2002(g)+ 3H2O(1)

Answer 1

cíven vol = 267161 presure = 4.21 atm. AB = 69.7KJ 3 69700 J uring AE = Otw S AE=change in internal Eneron 0 669.7 - 103.56) Q = Heat given that is exochied - 69-7 103.59 W = work done - 173.26 KJ s por 2-4-21 x 24.6 = 103.5G EJ 2) Quiven, mais of Hydrog carbon = 1.4959 molar mas gu = 108.19imal ex = 5294 lejlºc LAP 6.1744°C uring a = m G AT e m= mass of Hydrocarbon 7 incendi = 1,495 X 5.294 v6.744. puas x5.294 v6.744 doisprecht Heat capa'ala of = change in temp = 53.37 kutoped mole of hydrocarbon = 1.495 = 0·0825-male 108 Son - 53.37- KJ 646.909 kJ/mole 0.0825 mol DH= DE + PAV or AH = AE + NR 8T) where in= maille 3) e reactand