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Researched by Chrisitine C. 1999-2000 |
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PURPOSE
The purpose of this experiment was to determine if cubes of ice with
the same volume, but different surface area would have the same melting
speed.
I became interested in this idea when I noticed that ice cubes in soft
drinks melted at different speeds depending on size and shape.
The information gained from this experiment may help restaurants and
other food services save electricity when freezing the ice cubes and not
having to put as much ice cubes in the soft drinks.
HYPOTHESIS
My hypothesis is that a cube of ice with a volume of 1000mL, and a surface
area of 600cm2 will melt slower than ice cubes with the same volume, but
different surface areas of 616cm2, 738cm2, 1,4982cm2, an 2,569cm2.
I base my hypothesis on information I read that cubes of ice with less surface area will melt slower. Ice that has very low surface area has more ice concealed inside than it does on the outside.
EXPERIMENT DESIGN
The constants in this study were:
*The same volume of
water in the ice cubes
*The same temperature
of the freezer
*The same type of
surface the containers were set on
*The same source of
water
*The same type of
material in the ice/water containers
*The same room temperature
when melting the ice
The manipulated variable was the different surface areas of the cubes
of ice.
The responding variable was the time it took the ice cubes to melt completely.
To measure the responding variable, the melting will be timed, in seconds and minutes.
MATERIALS
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PROCEDURES
1. Gather all materials needed.
2. Label all containers that will contain water for freezing.
3. Place 1000mL of bottled spring water in container measuring 10.2cmx10.2cmx10.2cm.
4. Set in freezer carefully so no water spills out with a temperature
of 0°C.
5. Let it freeze for 12 hours.
6. After 12 hours have passed, take out the ice and set it in container
measuring 20cmx20cmx20cm in a room temperature of 69°F.
7. Start stopwatch immediately.
8. After the ice has completely melted, stop the stopwatch.
9. Record data.
10. Repeat steps 3-9 for the containers measuring 14cmx8.3cmx9.1cm,
15.9cmx15.2cmx4.2cm, 15.9cmx15.9cmx4.2cm,and
28.6cmx15.2cmx2.4cm.
RESULTS
The original purpose of this experiment was to determine if cubes of
ice with the same volume, but different surface area would have the same
melting speed.
The results of the experiment were that an ice cube with measurements
of 600cm2 would melt slower than ice cubes that had the same volume of
water but more surface area.
See the graph below.
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CONCLUSION
My hypothesis was that a cube of ice with a volume of 1000mL, and measurements
of 600cm2 would melt slower than blocks of ice with the same volume but
measurements of 616cm2, 738cm2, 1,498cm2, and 2,569cm2.
The results indicate that this hypothesis should be accepted.
Because of the results of this experiment, I wonder if the temperature
of the water would have had any affect on how fast the water would freeze.
If I were to conduct this project again, I would have done the experiment twice and seen if the data would have been the same.
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RESEARCH REPORT INTRODUCTION Water is known as H20. When frozen it then becomes ice. Ice freezes at 0°C or 32°F. Water can dissolve into almost all substances. Thermodynamics is when forms of energy are added and then taken away, not changing the temperature of all the forms of energy added together. The melting point and freezing point is when substances change from a liquid to a solid or a solid to a liquid. Heat capacity is the amount of energy for a substance to change in temperature. WATER Water is known chemically as H20 because two atoms of hydrogen are bonded with one oxygen atom. This makes it an oxide of hydrogen. Water is a liquid without color, taste, or odor. It begins to freeze at 0°C or 32°F. When ice is frozen, it expand 1/11 (or 9%) of its volume. Water is the only substance that can be three different forms at normal human temperatures: liquid, solid, or gas. The molecules in water are always moving. The molecules in ice are almost motionless and spread out, forming a pattern. The molecules in water vapor are constantly bumping in to one another and move about aggressively. Water’s boiling point is 100°C (212° F). Water is at its maximum density at 4° C (39°F). ICE Ice is colorless and odorless. It is known as water in its solid state.
When water is at 4° C (39° F) or above it contracts, but when below
4° C (39° F) it then starts to expand. When water reaches 0°
C (32° F), it then forms into ice. This is why ice floats in water,
because it expands and becomes lighter. If water was to contract during
freezing, it would then become heavier than water and it would then sink.
THERMODYNAMICS Thermodynamics is the study of various forms of energy, such as heat,
and the conversion of that energy from one form to another. There are two
main laws, or principles of thermodynamics. The first law says that the
total energy in a system stays constant. It can’t increase or decrease
but it can move or change forms. That means that ice can get warmer and
melt but something else like the air or the table surface must get colder
to match. The second law says the heat will flow only in one direction,
from a hotter object to a colder object. This means that heat in the air
and table surface flow into the ice. The coldness in the ice does NOT flow
anywhere.
MELTING POINT / FREEZING POINT The temperature at which a substance changes from a solid to a liquid is called the melting point. The same temperature is its freezing point. Water's melting and freezing point is 32°F or 0°C. At this temperature both liquid water and solid ice can exist together. DISSOLVING ABILITY Water dissolves into most substances. It can dissolve rocks by moving over them and bringing the materials to the ocean. Water brings the nutrients into the soil that helps plants grow. Water can even dissolve the food in your stomach. HEAT CAPACITY Heat capacity is the amount of heat a substance must absorb in order for its temperature to change. Some substances require a lot of heat to change. Others take much less. Water has the highest heat capacity of any substance, except for ammonia. SUMMARY Water is an important substance on the earth. Water is important scientists to study, because it is so important to people. BIBLIOGRAPHY Boehm, Robert F. "Thermodynamics" The World Book Encyclopedia, 1991 Chesick, John P. "Freezing Point" The World Book Multimedia Encyclopedia, 1999. Chesick, John P. "Melting Point" The World Book Multimedia Encyclopedia, 1999. Gardner, Robert "Experimenting with Water" NY, 6+ Franklin Watts, 1993. Hartman, Robert F. "Ice" The World Book Multimedia Encyclopedia, 1995 "Ice" Microsoft Encarta Encyclopedia, 1999. Keinath, Thomas "Water" The World Book Encyclopedia, 1999 Lafferty, Peter "The Dictionary of Science" NY, Simon & Schuster, 1993 Lewin, Seymour Z. "Water" Microsoft Encarta Encyclopedia, 1999. "Molecule" The World Book Multimedia Encyclopedia, 1999. "Water" The World Book Multimedia Encyclopedia, 1999.
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