In: Chemistry
Write a reaction for the dissolution of fluorite (CaF2) in water. Calculate the change in enthalpy, entropy and free energy for this reaction at 25°C
Dissolution of CaF2 is
CaF2(s) + H2O(l) ------------------- CaF2(aq)
Chnage in enthalpy = H=
Hf
of CaF2(aq) - [
Hf of CaF2(s) +
Hf of H2O]
=-1184.07 -[-1219.64 -285.83]
H= 321.4 KJ
Change in entropy =S=
Sf
of CaF2(aq) - [
Sf of CaF2(s) +
Sf of H2O]
= 92.59 -[68.87+69.91]
S = -46.19J
G =
H -
T
S
T= 25C = 25+273 = 298K
G = 321.4KJ -
[298x(-46.19J)]
G = 335.164KJ
G = 335.16KJ.