Calorimetry: Heat of Fusion of Ice
William Meighan
Hour 1
Purpose:
The purpose of this lab was to find the heat of fusion of ice using a simple calorimeter.
Procedure:
Approximately 125-mL of tap water were heated in a 250-mL beaker with a Bunsen burner to
a temperature of 50°C . The water was then removed from the heat and 100-mL of the warm
water were measured out using a graduated cylinder. The volume of the measured water was
recorded as V1 and then placed in a styrofoam cup that served as a simple calorimeter. The
temperature of the water was then measured using a temperature probe connected to a Labpro
calculator interface and recorded as T1.
Three ice cubes were immediately added to the warm water in the styrofoam cup calorimeter.
The ice-water mixture was constantly stirred and the temperature monitored until it leveled off.
Ice cubes were added to the mixture as the original ice cubes began to melt in order to maintain
an ice-water mixture. When the temperature of the mixture leveled off, the temperature was
recorded as T2. The remaining ice cubes in the mixture were then removed and the volume of
water in the calorimeter was measured with a graduated cylinder and recorded as V2.
Observations & Data:
V1 = 100.1 mL
V2 = 163.2 mL
T1 = 49.7°C
T2 = 0.48°C
Calculations:
Mass (m1) of the original volume of water (V1) using the known density of water.
m1 = 100.1 mL x 1g/1mL = 100.1 grams
Volume of water resulting from the melted ice. (V = V2 – V1)
163.2 mL – 100.1 mL = 63.1 mL
Mass of water from melted ice (m2) using the known density of water.
m2 = 63.1 mL x 1g/1mL = 63.1 grams
Calculations (continued)
Change in temperature of the water. (∆T = T1 – T2)
∆T = 49.7°C – 0.48°C = 49.2°C
Heat lost by the original mass of water. (∆Q = m1 x ∆T x c)
∆Q = 100.1g x 49.2°C x 4.18 J/g.°C = 2.06 x 104 J
Heat of Fusion of Ice (∆Q/m2)
Heat of Fusion of Ice = 2.06 x 104 J/ 63.1 g = 3.26 x 102 J/g
Percent Error (accepted – experimental/accepted x 100)
336 J/g – 326 J/g / 336 J/g x 100 = 2.98 % error
Conclusions:
The purpose of this lab was accomplished since the heat of fusion of ice was found with only a
2.98% error. The percent error was low considering the equipment used in this lab. One
possible source of error for this lab was the Styrofoam cup that was used as a calorimeter. There
was no lid on the cup and heat could have been lost to the surroundings or heat could have
entered the cup from the top. Another possible source of error could have been in measuring the
volume of water used in the calorimeter. Since the measurements of volume using the graduated
cylinder have one estimated number, the estimated number could have been off resulting in an
incorrect volume. The temperature readings were taken using a digital temperature probe so
there was no estimated number in these measurements, but the digital temperature probe may not
have been accurate and this would have affected the results. Another possible source of error
could have come in measuring the final volume of water in the calorimeter. The final volume
was greater than a 100 mL graduated cylinder would hold so the graduated cylinder was filled
and measured and then poured out and refilled with the remaining volume of water. There could
have been a small amount of water left in the graduated cylinder from the first filling and this
would have thrown off the second measurement of water in the cylinder. Overall, the lab went
well with no major problems and a reasonable heat of fusion of ice was found, so the lab was a
success.