Question

Differentiate between homogeneous and heterogeneous solidification phenomenon

Answer 1

Unlike homogeneous nucleation, heterogeneous nucleation occurs when the nucleus is on the surface. As previously stated, heterogeneous nucleation is more common than homogeneous nucleation. ... This is because the nucleation barrier comes from the positive term in the free energy ΔG, which is the surface term.

Answer 2

A reaction between two gases or two miscible liquids is homogeneous. A reaction between a gas and a liquid, a gas and a solid or a liquid and a solid is heterogeneous. ... In homogenous nucleation you form an entirely new surface directly, while heterogenous nucleation takes place on already existing surface (growth).