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The only thing that is given is:

The enthalpy of vaporization for $N_2(l)$ is 5.56 kJ/mol.

There aren't any examples similar to this problem in the textbook. I only know how to get energy using:

$q=mcΔT$ and $w=PΔV$

No clue what to do with the enthalpy of vaporization value.

UPDATE: Solved it by first getting number of moles ($n$) via $PV=nRT$ then multiplying moles by 5.56 kJ/mol. Moles cancel out, leaving only kJ, 1.75kJ to be precise.

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Since nitrogen's boiling point is 77.36 K , it appears that the question is asking how much heat is required to boil nitrogen to produce 2.0 L at 1 atm.

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  • $\begingroup$ Sorry but it doesn't help much $\endgroup$
    – Twilight Pony Inc.
    Commented Apr 19, 2014 at 18:52
  • $\begingroup$ Using the ideal gas law, how many moles of nitrogen are in 2.0 L at 1 atm and 77.36 K? Then find the amount of heat needed to convert that amount from liquid to gas. $\endgroup$
    – LDC3
    Commented Apr 19, 2014 at 19:00
  • $\begingroup$ Once i get the # of moles, which formula do i need to apply to get heat? $\endgroup$
    – Twilight Pony Inc.
    Commented Apr 19, 2014 at 19:33
  • $\begingroup$ @TwilightPonyInc. You should have used the equation. A favorite problem involves heating ice to the freezing point, melting the ice, and then heating the water to a defined temperature. When you melt the ice, that is the equation you want. $\endgroup$
    – LDC3
    Commented Apr 19, 2014 at 19:37

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