Thermodynamics chemical reaction problem

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Homework Statement


What are q and w (in kJ) for the reaction of 22 g of Na(s) and 82 g of Cl2(g) to produce NaCl at 1 atm and 298 K.


Homework Equations



w=-delta(n(g))* R*T where delta(n(g)) = the moles of gas created during the reaction

The Attempt at a Solution



First, I wrote the chemical reaction for Na and Cl2

2Na(s) +Cl2(g)=> 2NaCl

delta(n(g))=0-1 = -1

82 g Cl2*(1 mol Cl2/70.98 g Cl2)*(-1 mol gas/1mol Cl2)= -1.16

delta n(g) =-1.16
w=-delta(n(g))*RT=(-1.16)(8.314)(298 K)=2.87 kJ

But that's not the answer according to the back of my textbook.
 
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The volume is changing from the volume of Cl2 gas to essentially zero.

Can one apply w = p [itex]\Delta{V}[/itex]? 1 mole of gas has a volume of 22.4 l.

Then there is the heat.
 
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