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1. By: Donald Shehu Friday, February 13, 2009
EFFECT OF H E A TH E A T ON THE
TEMPERATURE OF M E L T I N G I C EM E L T I N G I C E

2. The purpose of this activity is to observe the patterns in the temperature as the
ice melts.
(Included in attached lab handout)
a. Prepare a data table with the headings “Time” and “ Temperature”
b. Half fill a 250 mL beaker with crushed ice
c. Set up the apparatus as shown in the figure in the lab handout sheet. Be sure
the flame is very low.
d. Stir the ice continually. Use the stirring rod. Do not stir with the thermometer –
it may break.
e. Keep the thermometer near the centre of the beaker. Do not let it touch the
bottom.
f. Record the temperature every 30 s. Keep doing this until the ice is all gone.
g. Now keep recording the temperature every 30 s for 5-10 min after the ice is
gone.
h. Plot a temperature-time graph with time on the horizontal axis and temperature
on the vertical axis.

3. 1. Finely Crushed Ice 2. Beaker (1000 mL)
3. Thermometer 4. Glass Stirring Rod (Plastic)
5. Bunsen Burner 6. Clock with second hand
7. Ring Stand 8. Iron Ring

4. 9. Wire Gauze 10. Adjustable Clamp
11. String 12. Graph Paper
The results are included in the attached chart sheet.

5. 1. What happens to the temperature when the ice is melting?
The temperature slowly increases as the ice is melting.
2. What happens to the heat that the Bunsen burner put into the ice-
water mixture?
The heat, in the state of gas, gives off high energy to the ice, which is
in the state of a solid. This allows the particles in the ice to vibrate
faster and faster until the ice turns into liquid water. Then, if the heat
is still there, the particles in the water begin to move faster until the
water evaporates into gas.
3. Does the melting of ice require heat or does it require removal of
heat?
Ice does not require the heat of the Bunsen burner to melt, however
that heat aids in melting it at a quicker pace. Ice can melt naturally in
areas where the temperature is above 0°, which in this case the room
temperature is above 20°.
4. What is the melting point of ice? What happens to the graph at this
temperature? Why?
The melting point of ice is 0°C.

6. 5. What is the freezing point of water?
The freezing point of water is 0°C.
6. How are the melting point and the freezing point of a substance
related?
They both change the state of the substance at the same point of
degree, 0°C.
7. Why is melting point called a characteristic physical property?
Melting point is called a characteristic physical property because its
physical properties of a substance that make that substance
different from most other substances are called the characteristic
physical properties of that substance
8. The graph you plotted is called the heating curve for water. What
do you think the cooling curve would look like?

7. 9. a) Imagine a lake with large chunks of ice floating at the surface.
What will the temperature of the water be among the chunks of ice?
Why?
b) Will it be the same at the bottom of the lake? Why?
10. Under what conditions will ice be colder than 0°C?