PROBLEM : Will a decrease in heat energy cause water to freeze or melt?
BACKGROUND • Freezing temperature of water is: 32 F or 0 Celsius • Melting temperature of ice is: 32 F or 0 Celsius • Explain how the freezing & melting temperatures of water are related. They are both same temperatures because water can be all the states of matter • What are the states of matter? Solids, liquids, gas • Explain what causes substances to change from one state of matter to the next. The temperature that the object is in can affect the substance and make it change • What happens during the freezing process? The process when a liquid becomes a solid and the molecules contract/tighten • What happens during the melting process? The process when a solid becomes a liquid and the molecules expand • What is meant by the term “lower state of matter”? A solid • What is meant by the term “higher state of matter”? Plasma
BIBLIOGRAPHY: Dictionary.com | Find the Meanings and Definitions of Words at Dictionary.com . Web. 01 Oct. 2010.
Define the following terms: Physical Properties - any property used to characterize matter and energy and their interactions Freezing - the process by which a substance changes from a liquid to a solid Freezing point - the temperature where a specific liquid becomes a solid Melting - the process by which a solid becomes a liquid Melting Point - the lowest temperature when a substance melts
HYPOTHESIS - If the heat energy in the water decreases, then the water will freeze. Independent variable- heat energy Dependent variable- water DATA & OBSERVATIONS • Freezing temperature of water sample 0.2 °C
• Melting temperature of water sample 3 °C
ANALYSIS
1. What did this experiment help you understand or know about freezing and melting water? Give a detailed explanation. • We found out that the freezing and melting point of water is the same temperature.
2. How does your research support your data (give specific research facts & the data you collected to support them). How does your research conflict with your experiment data? • The research was not the same as our experiment because our freezing and melting point were different than they were supposed to be 32 degrees
3. What part does salt play in the freezing process? • Salt molecules bond with water molecules, making it more difficult for ice to form. The result is a solution with a lower freezing temperature.
4. If salt impacts/speeds freezing, why do road crews use salt to melt snow and ice on winter roads? • Salt lowers the temperature at which water freezes and melts. They use it because when the temperature lowers it makes the ice melts
5. What other chemicals can be used to melt ice? (find at least 2) Explain how one of them is used. • Magnesium- It attracts the moisture which makes the ice melt. • Calcium
CONCLUSION- Our hypothesis was if the heat energy in the water decreases, then the water will freeze. After testing our hypothesis we concluded that our experiment was a success. By adding ice and salt to the beaker that our test tube was sitting in it made the water freeze. When we put our test tube in the hot water it then made the ice melt. Our experiment proved that water can be in two different states of matter, a solid and a liquid.
SPECULATION- Will Gatorade take longer to freeze than water? If you freeze Gatorade, then it will take one minute and thirteen seconds longer than water to melt.