The addition of H2 to C=C double bonds is an important reaction used in the preparation of margarine from vegetable oils. If 57 mL of H2 and 57 mL of ethylene (C2H4) are allowed to completely react at 1.7 atm, the product ethane (C2H6) has a volume of 57 mL.

Calculate the amount of PV work done based on the following balanced reaction:

C2H4(g)+H2(g) C2H6(g)

Specify the direction of the energy flow.