What is the main characteristic of a heterogeneous mixture?

Correct answer: Having different composition in different parts

In a heterogeneous mixture, the components are not distributed uniformly, so different parts can have different compositions. For example, in a mixture of sand and water, sand may settle at the bottom while water remains above. Option A describes a homogeneous mixture, not a heterogeneous one. Exam tip: A mixture in which components or layers can be distinguished is generally heterogeneous.