What is the relationship between kinetic energy and thermal expansion?

These molecules are always in motion and higher temperature gives them more energy and they vibrate more rapidly and hence have higher kinetic energy. One effect of this rapid motion (high kinetic energy at higher temperatures) is the expansion observed, when we heat a substance.

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the "dirty dozen" chemicals banned in an international treaty are formally known as persistent organic pollutants, or pops. the united nations environment program provided this background on what they are and what they can do to humans and wildlife.

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