For the given system, (a) with dG = 0 dG = dH - TdS dH = TdS T (temperature) = d
ID: 700141 • Letter: F
Question
For the given system,
(a) with dG = 0
dG = dH - TdS
dH = TdS
T (temperature) = dH/dS
with,
dH = -14.9 kJ/mol
dS = -50 J/K.mol = -0.05 kJ/K.mol
we get,
Temperature (T) = -14.9/-0.05 = 298 K
So the reaction would be spontaneous below 298 K
(b) dG = dH - TdS
Using Van't Hoff relation,
lnK = -dH/RT + dS/R
with K = 3.0
R = gas constant
feeding dH and dS from above,
ln(3.0) = -(-14900/8.314 x T) + (-50/8.314)
ln(3.0) = = 1792.16/T - 6.014
Temperature (T) = 252 K
= 252 - 273 = -21 oC