Thermodynamics Concept Test

Problem 1

A piston is connected to a drive train that causes a car to move. The flame below is turned on, which heats up the gas causing it to expand. Engine diagram The signs of q and w for the gas in the cylinder are:

  1. q +     w +
  2. q +     w -
  3. q -     w +
  4. q -     w -

Problem 2

Consider burning acetylene:
C2H2(g) + 3/2O2(g) <---> CO2 (g) + H2O(l) ΔH = -1301.1 kJ
What is ΔH for the reaction:
2CO2(g) + 2H2O(l) <---> 2C2H2(g) + 3O2(g)

  1. ΔH = -2602.2 kJ
  2. ΔH = -1301.1 kJ
  3. ΔH = 1301.1 kJ
  4. ΔH = 2602.2 kJ