Why does matter contracts when cooled

For example, bridges expand in the summer heat and need special joints to stop them bending out of shape. When substances expand or contract, their particles stay the same size. It is the space between the particles that changes:. Remember, the particles themselves never expand.

Expansion and contraction Substances expand increase in size when they get warmer, and they contract decrease in size when they get cooler. To unlock all 5, videos, start your free trial. Most matter expands when heated and contracts when cooled, a principle called thermal expansion. The average kinetic energy of the particles increases when matter is heated and this increase in motion increases the average distance between its atoms.

It is important to note that water does not follow the rule of thermal expansion. Water expands when it freezes because the crystalline structure of ice takes up more space than liquid water. Have you ever noticed when you put a warm bottle of soda into your refrigerator, come back in a couple of hours, it's buckled in and it's lost some of its volume?

Well you'll notice that especially if there's a lot of air in that bottle. What you're seeing is the result of thermal expansion or in this case thermal contraction and what that basically says is thermal expansion as an object is heated, molecules move faster and they gain kinetic energy and they bounce further away from each other and that results in an expansion of that object.

David Drayer. Dec 8, Explanation: As the molecules of a liquid are cooled they slow down. Related questions What are physical properties of liquids? What are some examples of properties of solids? What are some examples of properties of liquids? How do properties of halogens differ from noble gases?

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