What is a main difference between a mixture and a pure substance? a mixture is only a liquid, but a pure substance can be in any state. a mixture looks the same throughout, but a pure substance does not. a mixture can vary in composition, but a pure substance has a set composition. a mixture can be made up of a single compound, but a pure substance cannot.

A mixture can vary in composition, but a pure substance cannot. think of salad dressing in a bottle and then think of pure water.

the transfer of heat by electromagnetic radiation is called thermal radiation . it is usually carried out by electromagnetic waves in an energy range just below the visible spectrum, which is the infrared range.

so the answer would be radiation.

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