Answer: Sample A is classified as a pure substance, Sample B is identified as a homogeneous mixture, and Sample C is a heterogeneous mixture.
Explanation:
Homogeneous mixture: In these mixtures, all components are evenly distributed. For example: a sugar-water solution.
Heterogeneous mixture: In these mixtures, components are not uniformly distributed. For instance: a sand-water solution.
Pure substance: These are made from a single type of atom or molecule and are characterized by fixed boiling and melting points. Examples include diamond and pure sugar.
Sample A is a clear liquid evaporating at
with a consistent appearance. Thus, it is a pure substance.
Sample B is a clear blue liquid boiling at
that leaves behind blue crystals, resulting in a change in appearance. Hence, it is a homogeneous mixture
Sample C is an opaque, whitish liquid boiling at
, leaving white crystals, with dust settling at the bottom. Thus, it is a heterogeneous mixture.