Download Lab: Specific Heat of Copper

Lab: Specific Heat of Copper
Name:
BIG IDEA: The heat lost by the metal = the heat gained by the water, or, -qm = qw.
Therefore, -mmcm∆Tm=mwcw∆Tw.
Introduction:
The specific heat of a substance is the amount of energy in calories or Joules required for one gram of that
substance to increase one degree Celsius. The specific heat of water is 4.184J/g-°C or 1 calorie/g-°C.
Water has a very high specific heat compared to many other substances. Study the chart below.
Amount of
energy
4.184 J
4.184 J
4.184 J
4.184 J
4.184 J
4.184 J
4.184 J
Mass of
substance
1.0 g
1.0 g
1.0 g
1.0 g
1.0 g
1.0 g
1.0 g
Substance and specific heat
Water
Aluminum
Iron
Silver
Tin
Lead
Gold
4.184
0.900
0.448
0.236
0.220
0.138
0.128
Temperature change
of substance
1.0°C
4.6°C
9.3°C
17.7°C
19.0°C
30.3°C
32.7°C
For example, 4.184J will raise only one gram of water 1 Celsius degree, while that same amount of energy
will raise one gram of gold 33 Celsius degrees! This high specific heat value of water means that water
will heat up and cool down slowly. This property helps moderate temperatures around coastal areas.
During summer the water is absorbing heat from the warmer air keeping the shore cooler, and then
releasing heat to the cooler air in winter, keeping the shore warmer.
In this lab a copper cylinder will be heated and cooled to find the specific heat of copper metal. Copper
metal is often used as a metal coating for pots and pans.
Procedure:
1. Obtain a copper metal cylinder. Obtain the mass of the metal and record.
2. Obtain 250 mL beaker and half fill with water. Using a test tube holder, carefully place metal into beaker.
3. Use a hot plate to heat the beaker of water and metal to boiling. Do procedure steps 4-6 while heating the
beaker.
4. Obtain 2 foam cups: 1 with a hole and 1 without a hole. Set the cup with the hole to the side for now.
5. Mass the cup without the hole and record. Then half fill the cup with tap water. Obtain the mass of the cup
and water. Record.
6. Take the temperature of water in the foam cup. Record.
7. When the beaker water is boiling, carefully remove from the hot plate using tongs. Place beaker on clean,
dry lab table. Take the temperature of water in the beaker. This will also be the temperature of the metal.
Record.
8. Immediately transfer the metal to the foam cup by using a test tube holder. Place the foam cup with hole on
top of cup with water. Slide stirring rod into hole and gently stir for three minutes. Remove stirring rod
and insert thermometer. Record temperature of water and metal.
Data:
Mass of metal
Mass of foam cup
Mass of foam cup and water
CALCULATE: Mass of only the water
Temperature of water in foam cup (Ti of water) before
metal added
Temperature of metal in beaker (Ti of metal) AFTER
boiling
Temperature of water and metal in cup (Tf of both the
water and the metal) at the end after three minutes
CALCULATE ∆T of the water
CALCULATE ∆T of the copper
Calculate the Specific Heat of the Copper here:
Conclusion:
1.
The specific heat of water is (high/low) when compared to many other substances.
2. Water keeps temperatures in coastal areas more moderate by ______________________________ heat during
summer and __________________________ heat during winter
3. Metals tend to have (high/low) specific heats.
4. Copper is a good choice for coating pots and pans because a small mount of heat will make a (small /
large) change in the temperature of the copper metal.
5. If sample A and sample B both absorb 100 joules of heat and sample A changes one Celsius degree and
sample B changes ten Celsius degrees, which sample has the highest specific heat? ______________
Use the chart on the front of the page to help answer the following question:
6. If ten grams of aluminum and ten grams of iron both cool from 70°C to 60°C, which substance will release
the most heat? ______________________________
Complete the chart below:
Amount of energy
(heat)
Mass of substance
Substance and Specific
heat in J/gCo
Temperature change of
substance
7
__________________ J
100.0 g
Water – 4.184
5.0°C
8
450J
100.0g
Aluminum – 0.900
__________________°C
9
44 J
____________ g
Iron – 0.448
9.8°C