What is easier to separate a homogeneous mixture or a heterogeneous mixture?

The difference in the size of their particles

Heterogeneous mixtures are easier to separate because the particles sizes of the components of the mixture differ greatly and such the separation technique used can take advantage of this property.

An example frequently used is Sand and water. Simply filtration with filter paper and funnel brings about this separation as the water particles are small enough to pass through the paper, however the sand particles are too large and are stopped from passing. After a few moments, the water and sand would have been fully separated.

Homogenous mixtures are harder to separate because the particles sizes are close in relation to each other and as such this property would not be ideal for the separation technique used.

This is when the experimenter will turn to other properties such as boiling points, melting points and solubility in order to separate them.

An example would be to separate salt from water.

The technique preferred is evaporation as the boiling points of H2O(100oC) and NaCl(1413oC) are far apart and thus would cause the evaporation of the water longer before the NaCl begins to evaporate.