Question

15. When gasoline burns in a car engine, the heat released causes the products CO2 and H20 to expand, which pushes the pistons outward. Excess heat is removed by the car's radiator. If the expanding gases do 478.9 J of work on the pistons and the system releases 846.8 J to the surroundings as heat, calculate the change in energy (AE) in J, KJ, and kcal. (4.0 pts) Energy change Your solutions (AE-+ w) (1 cal = 4.184 J, 1 kcal = 4.184 kJ) In J In kJ In kcal In cal

Answer 1

Cif work is done on W = - 478.9 JTD the system (energy addet'ho system) 9, 3-8468.J work is negative, C (Heat releases from the DE = qtw systems then q is negohve ). = -846.8 J +6–478.93) -1325. I J Energy change in J. -1325.7 J are 87 o = Energy change in KJ = -1325.7 J xk J 103J = -1.325J kJ

Energy chonge in kcal i = -1.3257 kJ. kcal 4.184 kJ ; -.31685 kcal Energy change in cal = -0,3168.5 kcal x 10° 3 - 316185 cal