Which description correctly defines a homogeneous mixture?

Which description correctly defines a homogeneous mixture?

• A. A mixture with varying composition throughout.
• B. A pure substance with constant composition.
• C. A uniform mixture with the same composition throughout.
• D. A mixture where components settle out.

Answer: (C)

A homogeneous mixture is one that has a uniform composition throughout. That means no matter where you take a sample, the proportions of the substances are the same and you can’t see different parts with the naked eye. Examples include salt dissolved in water or the air you breathe—clear, consistent mixtures where everything is evenly distributed. The description that fits this idea is a uniform mixture with the same composition throughout. A pure substance, by contrast, has a single kind of particle and is not a mixture. A mixture where components settle out describes a heterogeneous situation where different parts become distinct over time, so the composition isn’t the same everywhere. A mixture with varying composition throughout is also heterogeneous, not uniform.

A homogeneous mixture is one that has a uniform composition throughout. That means no matter where you take a sample, the proportions of the substances are the same and you can’t see different parts with the naked eye. Examples include salt dissolved in water or the air you breathe—clear, consistent mixtures where everything is evenly distributed.

The description that fits this idea is a uniform mixture with the same composition throughout. A pure substance, by contrast, has a single kind of particle and is not a mixture. A mixture where components settle out describes a heterogeneous situation where different parts become distinct over time, so the composition isn’t the same everywhere. A mixture with varying composition throughout is also heterogeneous, not uniform.