Question

# THERE IS NO OTHER INFORMATION GIVEN BESIDES 298K Exercise 19.87 The following reactions are important ones...

THERE IS NO OTHER INFORMATION GIVEN BESIDES 298K

Exercise 19.87

The following reactions are important ones in catalytic converters in automobiles. Calculate ΔG∘for each at 298 K. Predict the effect of increasing temperature on the magnitude of ΔG∘.

Part A

2CO(g)+2NO(g)→N2(g)+2CO2(g)

ΔG∘rxn =   kJ

Part B

 ΔG will increase with increasing temperature. ΔG will decrease with increasing temperature.

Part C

5H2(g)+2NO(g)→2NH3(g)+2H2O(g)

ΔG∘rxn =   kJ

Part D

 ΔG will increase with increasing temperature. ΔG will decrease with increasing temperature.

Part E

2H2(g)+2NO(g)→N2(g)+2H2O(g)

ΔG∘rxn =   kJ

Part F

 ΔG will increase with increasing temperature. ΔG will decrease with increasing temperature.

Part G

2NH3(g)+2O2(g)→N2O(g)+3H2O(g)

ΔG∘rxn =   kJ

Part H

 ΔG will increase with increasing temperature. ΔG will decrease with increasing temperature.

Part A : 2CO(g)+2NO(g)→N2(g)+2CO2(g) : ΔGorxn = ?

ΔGorxn = ΔG0fproducts – ΔG0freactants

ΔGorxn = [(ΔG0fN2(g) )+ (2 x ΔG0fCO2 (g) )]- [( 2 x ΔG0fCO(g) )+ (2 x ΔG0fNO (g) )]

= [(0)+(2x(-394.4))] - [(2x(-137.3))+ (2x(86.6))] kJ/mol

= -687.4 kJ

Part B : Since ΔGorxn is negative upon increase in temperature ΔGorxn also increases

Part C : 5H2(g)+2NO(g)→2NH3(g)+2H2O(g) : ΔGorxn = ?

ΔGorxn = ΔG0f  products – ΔG0f  reactants

ΔGorxn = [(2xΔG0f  NH3(g) )+ (2 x ΔG0f  H2O (g) )]- [( 5x ΔG0fH2(g) )+ (2 x ΔG0f  NO (g) )]

= [(2x(-16.5))+(2x(-228.6))] - [(5x0)+ (2x(86.6))] kJ/mol

= -663.4 kJ

Part D : Since ΔGorxn is negative upon increase in temperature ΔGorxn also increases