1. BIGGER BRRRR! Does water expand when it freezes? Purple team 4 th grade Mrs. Johnson Northview Elementary School

2. STATEMENT OF THE QUESTION Does water get larger, or expand, when it freezes?

3. PROJECT OVERVIEW We have been studying weathering in our science class. Weathering is when rock breaks down into smaller pieces. Our text says one of the causes of weathering is water that seeps into the cracks of rocks and freezes. When it freezes, it expands and breaks the rock. We will test this idea. We will measure the water in several containers, and then freeze it. We will then measure the water again.

4. RESEARCH The most important ideas from our research were: -Water can exist as a solid, liquid, or gas. -When water freezes, it changes from a liquid to a solid we call ‘ice’. -Freezing water can cause serious problems for people. For example, when water in water pipes freezes, it can cause the pipes to burst. -Most materials contract, or get smaller as they get colder, and expand, or get larger when they heat up.

5. VARIABLES CONTROLLED variables – these variables will be kept the same: - type of water - type of container - time in freezer - position in freezer - amount of water in container INDEPENDENT variable – this variable is the one we changed on purpose: - temperature

6. V VARIABLES, CONTINUED Dependent variable - level of water in graduated cylinder

7. PREDICTION OR HYPOTHESIS We predict that the water WILL expand because many of us have put plastic water bottles in the freezer. When we take them out the next day, sometimes the bottom of the bottle sticks out so the bottle can’t even stand up. Sometimes, the bottle actually breaks in the freezer. We think this is because the water expanded as it froze.

8. MATERIALS 6 graduated cylinders Water from the tap Black sharpie Freezer

9. PROCEDURE 1. Each table will fill a graduated cylinder with water up to the 20 ml mark. 2. Each table will label their cylinder with their table letter. 3. We will place all of the cylinders in the freezer in the teacher lounge. 4. We will leave the cylinders over night. 5. The next day we will remove the cylinders and measure the level of the water.

10. DATA/OBSERVATIONS Table A Table B Table C Table D Table E Table F Starting Height 20 ml Ending Height 22 ml21 ml22.5 ml22 ml21 ml23 ml Change+2+1+2.5+2+1+3 CHANGE IN HEIGHT OF WATER BEFORE AND AFTER FREEZING

11. CONCLUSION The level of water in all of our cylinders was higher after we froze the water. So we concluded that the water DID expand as it froze. This explains why water pipes can burst if the water in them freezes. We would like to continue our investigation by measuring the water level in our cylinders each day for 2 weeks after we remove them from the freezer. We hope to observe the process of evaporation in which the liquid water changes to gas.

12. WORKS CITED Black, Peter. Water Drops. New York: SUNY Press, 2012. Kids Konnect website: 2012. Online. 10 Sep. 2012. Available: http://www.kidskonnect.comhttp://www.kidskonnect.com Science for Kids website: 2012. Online. 10 Sep. 2012. Available: http://www.sciencekids.co.nzhttp://www.sciencekids.co.nz Wick, Walter. A Drop of Water. New York: Scholastic Press, 1997.