Consider a given volume of liquid at a temperature ∆T below Tm with a free energy G₁, figure a. If Vs is the volume of the

solid sphere, V, the volume of liquid, Asl is the solid/liquid interfacial area, GS and G are the free energies per unit

volume of solid and liquid respectively, and Ysl, the solid/liquid interfacial free energy.

(a) The free energy of the system without any solid present is G₁=_______

(b) If some of the atoms of the liquid cluster together to form a small sphere of solid, figure b, the free energy of the

system will change to G₂ =_____

(c) Therefore, the formation of solid results in a free energy change ∆G =_______

(d) Determine the energy barrier AG* for homogenous nucleation using the information above.