What is ΔG°rxn in kJ/mol for the following reaction at 587.5 Kelvin? Please report 2 decimal places, without units. 2NO(g) + Cl2(g) → 2NOCl(g

Question

	Substance:	NO(g)	Cl2(g)	NOCl(g)
​	​	​	​
ΔH°f (kJ/mol) at 298 K	90.29	0	51.71
ΔG°f (kJ/mol) at 298 K	86.60	0	66.07
S°(J/K • mol) at 298 K	210.65	223.0	261.60

 

2NO(g) + Cl2(g) → 2NOCl(g)

Answer 1

Find ∆Hºrxn and ∆Sºrxn:

∑products - ∑reactants - NOTE: the format of your table is messed up, so hopefully I used the correct values. You need to double check that I did.

∆Hº = (51.70 x 2) - [(90.29 x 2) + 0)] = 103.4 - 180.6

∆Hºrxn = -77.2 kJ

∆Sº = (0.262 x 2) - [(0.211 x 2) + 0.223] = 0.524 - 0.645

∆Sºrxn = -0.121 (NOTE: changed units of ∆S to kJ/K-mol instead of J/K-mol)

At 587.5K, we can find ∆G as follows:

∆G = ∆H - T∆S

∆G = -77.2 - T(-0.121)

∆G = -77.2 - (587.5 * -0.121)

∆G = -77.2 + 71.1

∆G = -6.1 kJ/mol