What is the enthalpy of vaporization of the compound?

Question

A 4.00 L sample of gas at 250 degrees celsius and 0.790 atm condenses to give 1.20 mL of liquid; 600 J of heat is released during the process. What is the enthalpy of vaporization of the compound? I'm not sure how to approach this problem because volume is given in it and I don't know if there is a certain equation I should use. Showing the steps on how to solve this problem would greatly be appreciated, Thank You.

Answer 1

I wonder why no one try this to help you.
Approximating the initil gas as the ideal gas give us the information of the quantity of the sample:
n = PV/RT = 0.790*4.00/(0.08206*523.2) = 0.0736 (Mol)
The enthalpy of vaporization is:
600J/ 0.0736 Mol = 8.15 kJ/Mol