What Is the Most Efficient Substance for Melting Ice
To determine the most effective of seven substances traditionally used for melting ice.
- 14 aluminum foil baking pans (8 × 8 × 2 inches) (20 × 20 × 5 cm)
- tap water to fill each pan
- masking tape
- marking pen
- 1 cup (0.24 liter) calcium chloride
- 1 cup (0.24 liter) of a commercial brand of melting crystals
- 1 cup (0.24 liter) sodium chloride
- 1 cup (0.24 liter) cat box litter
- 1 cup (0.24 liter) sand
- 1 cup (0.24 liter) rubbing alcohol
- 1 cup (0.24 liter) mineral rock salt
- large freezer (experiment can be done outside if temperature is below 32° F or 0°C)
Fourteen aluminum foil baking pans containing ice will be subjected to equivalent amounts of different substances commonly used to melt ice. Each pan will be timed individually so as to determine which substance, and the way it is applied, is the most effective in melting the ice. Comparisons will then be made between each substance to see the amount of residue each has left and whether that residue could have damaging effects on paved driveways and sidewalks.
- Fill seven of the baking pans with water and freeze them either in a large freezer or outdoors. Label this lot Group A.
- Pour one-half of each of the seven substances separately into the remaining seven baking pans. Label each pan with the name of its substance. Carefully fill the pans with water and place them in the freezer or outdoors to freeze. Label this lot Group B.
- When the water in Group A has completely solidified, pour the remaining half of each substance into the separate pans. Label each pan with the name of its substance and return them to the freezer.
- At this point, all 14 pans of water/ice will be in contact with one of the substances. Measure the amount of melting of each pan in Group A in half-hour intervals over a 3-hour period and record your results. Check on Group B in half-hour intervals also, noting the rate of ice formation, if any, over a 3-hour period. Record your results.
- Pour some of the contents of each baking pan in Group A onto separate sections of a uniformly paved driveway and label. Pour some of the contents of the Group B pans into separate sections of a uniform cement sidewalk and label. Allow all of the water to evaporate. Let the different types of residue stay where they are for 4 to 6 weeks. After this time, sweep them away and note any damage that has resulted. Compare the effects of the same substances on both surfaces.
- Which substance in Group A melted the ice fastest? How well did this substance prevent the formation of ice in Group B?
- Did the addition of the ice-melting substances prior to the application of water in Group B slow or prevent the formation of ice? Does this mean that such substances should be applied to driveways and sidewalks when precipitation and freezing temperatures are expected?
- Did any of the substances' residues cause damage to either the paved driveway or the sidewalk? If so, what type of damage did you observe?
- In terms of speed, efficiency, and cost, which substance was the best?
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