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posted by  op on 4/12/2008 11:26:23 PM  |  status: Closed  

Need help!! will rate high!!

Course Textbook Chapter Problem
General Chemistry N/A N/A N/A
Question Details:
Use capital deltaG°f values to calculate the free energy change at 25°C for each of the following reactions. (a) H2(g) + I2(g) 2 HI(g)
kJ

(b) N2(g) + 3 H2(g) 2 NH3(g)
kJ

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posted by tee#1 on 4/12/2008 11:59:42 PM  |  status: Live
Asker's Rating: Helpful   
op's comment:
"Thanks but the value you calculated for part a was incorrect but I figured out the right answer from your work."
Response Details:
ΔGrxn= Σ n ΔGf products -Σ n ΔGf reactants
 
a) ΔGrxn = 2 ΔGf HI(g) - [ΔG H2(g) + I2(g) ]
              =2(1.72 kJ/mol) -[0+0] = + 3.44 kJ/mol for the rxn as written
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posted by tee#1 on 4/13/2008 12:02:11 AM  |  status: Live
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Response Details:
b)  
ΔGrxn= Σ n ΔGf products -Σ n ΔGf reactants
 
a) ΔGrxn = 2 ΔGf NH3(g) - [3ΔG H2(g) + N2(g) ]
              =2(-16.5 kJ/mol) -[0+0] = -33.0 kJ/mol)for the rxn as written
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posted by astronaut on 4/13/2008 12:06:19 AM  |  status: Live
Asker's Rating: Somewhat Helpful   
Response Details:
a) 3.44 KJ / mol
 
b) -34 KJ/mol
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