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? How are atoms arranged in metals? Use the particle model to explain expansion and contraction of solids, liquids and gases. Compare expansion and contraction in solids, liquids and gases.
Describe some practical and safety considerations associated with the expansion and contraction of matter. Image: GT, Wikimedia Commons. Lesson Topics 1 Expansion and Contraction 2 Expansion and Contraction in Solids 3 Expansion and Contraction in Liquids 4 Expansion and Contraction in Gases Lesson Summary When a substance absorbs or loses heat energy, the movement of its particles is affected, which causes its volume to change.
Blow up a balloon until it is mostly—but not completely—full. Then carefully tie it off with a knot. With your helper assisting you, measure the circumference of the widest part of the balloon using a cloth tape measure or a piece of string and then measure the string against a tape measure. Pinch the opening closed between your thumb and finger so the air cannot escape. Then tie off the second balloon. Procedure Turn one of the balloons so you can look at the top of it.
At the very top it should have a slightly darker spot. Using the permanent marker, carefully make a small spot in the center of the darker spot.
Then take a cloth tape measure or use a piece of string and a regular tape measure or ruler and carefully make two small lines with the permanent marker at the top of the balloon that are two and one half inches away from one another, with the darker spot as the midpoint.
To do this you can center the tape measure so that its one-and-one-quarter-inch mark is on the small spot you made and then make a line at the zero and two-and-one-half-inch points.
Repeat this with the other balloon so that it also has lines that are two and one half inches apart on its top. For example, the distance might be two and three eighths inches or two and five eighths inches.
Put balloon number 1 in the freezer in the area you cleared out for it. Leave it in the freezer for 45 minutes. Do not disturb it or open the freezer during this time. How do you think the size of the balloon will change from being in the freezer?
During this time, leave balloon number 2 somewhere out at room temperature not in direct sunlight or near a hot lamp. After balloon number 1 has been in the freezer for 45 minutes, bring your cloth tape measure or piece of string and regular tape measure to the freezer and, with the balloon still in the freezer but with the freezer door open to let you access the balloon , quickly measure the distance between the two lines as you did before.
Did the distance between the two lines change? If so, how did it change? What does this tell you about whether the size of the balloon changed? Why do you think this is? Then measure the distance between the two lines on balloon number 2, which stayed at room temperature. Overall, how did the balloon change size when placed in the freezer? What do your results tell you about how gases expand and contract as temperature changes?
Extra: After taking balloon number 1 out of the freezer leave it at room temperature for at least 45 minutes to let it warm up.
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