Experimens related to latent heat
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You will first need to obtain some ice. Let the ice sit in a bowl at room temperature until you notice that it is starting to melt. This will probably take 15 to 20 minutes. In a freezer, ice is kept at a temperature well below freezing (typically near 0o F). We need to allow the ice to sit outside the freezer long enough that is warms up to freezing (0o C or 32o F). The ice can't get warmer than freezing; once it reaches freezing it will start to melt.
Add 200 to 250 mL of warm tap water (40o C or less so that there isn't too big of a temperature difference between the water and air) to the styrofoam cup. We keep the warm water in a styrofoam cup to minimize the loss of heat to the cooler surroundings. Keep a record of the actual amount of water added to the cup. Measure and record the temperature of the warm water just before you are ready to add some ice.
Add one or two ice cubes (or about 1/4 cup of crushed ice) to the warm water and stir gently with the thermometer until the ice is completely melted. Try to be sure you just add ice and none of the water in the bowl from the melted ice. Once the ice in the cup has melted, measure and record the water temperature. If the temperature has dropped to near freezing or if you are unable to melt all of the ice, you will need to repeat the experiment. You will need to use less ice or more water or both.
Use the graduated cylinder to measure the new volume of the water in the styrofoam cup. This new volume will be larger than the initial volume because it contains the water from the melted ice. Because water has a density of 1gram/mL (1 gram/cm3) there is a one to one relationship between a measurement of water volume in mL and the mass of the water in grams. The difference in the starting and ending water volumes is the mass of the ice that was melted.
Repeat the experiment at least one more time using a different amount of water, a different amount of ice, and perhaps a different initial water temperature.
Add 200 to 250 mL of warm tap water (40o C or less so that there isn't too big of a temperature difference between the water and air) to the styrofoam cup. We keep the warm water in a styrofoam cup to minimize the loss of heat to the cooler surroundings. Keep a record of the actual amount of water added to the cup. Measure and record the temperature of the warm water just before you are ready to add some ice.
Add one or two ice cubes (or about 1/4 cup of crushed ice) to the warm water and stir gently with the thermometer until the ice is completely melted. Try to be sure you just add ice and none of the water in the bowl from the melted ice. Once the ice in the cup has melted, measure and record the water temperature. If the temperature has dropped to near freezing or if you are unable to melt all of the ice, you will need to repeat the experiment. You will need to use less ice or more water or both.
Use the graduated cylinder to measure the new volume of the water in the styrofoam cup. This new volume will be larger than the initial volume because it contains the water from the melted ice. Because water has a density of 1gram/mL (1 gram/cm3) there is a one to one relationship between a measurement of water volume in mL and the mass of the water in grams. The difference in the starting and ending water volumes is the mass of the ice that was melted.
Repeat the experiment at least one more time using a different amount of water, a different amount of ice, and perhaps a different initial water temperature.
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