Question

is milk a heterogeneous mixture or homogeneous mixture?

Answer 1

it is a homogeneous mixture

Answer 2

Milk is a colloidal solution.

The colloidal solution is a mixture that is actually heterogeneous mixture but appears to be a homogeneous mixture as the particles are uniformly spread throughout the solution.

Heterogeneous mixture -

The mixture which does not have the same composition throughout. The components are distributed uniformly. The components can be distinguished from each other.

Examples - Sand in water, iron nails in the sand, pebbles in rice.

Homogeneous mixture -

The mixture that has the same composition throughout. The components are distributed uniformly. The components can be distinguished from each other.

Examples - Salt in water, sugar in water.