Module 6
PlanningGuide
Lab 2.7
Lesson 2.5
Lesson 2.6
Lesson 2.7
Lesson 2.8
Lab 2.5
Lab 2.6
Lab 2.7
Lab 2.8
Project 6
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Physics
Lab 2.7 Heat Capacity of Steel
Overview
In this laboratory class we determine the specific heat
capacity of one material by allowing it to gain energy
from a known amount of water. The two materials reach
thermal equilibrium in an insulated container and the
energy lost by the water is assumed to be gained by the
second material.
Experiment
2.7.1 Heat Capacity of Steel
Equipment
Water heater
2 Insulated containers – flasks or foam cups.
Thermometer
Steel nails
Measuring cylinder
String
Procedure:
- Weigh about 150 grams
of steel nails and record the mass.
- Tie the nails
together with a piece of string and submerge the
nails in a container that has water in it at room
temperature.
- Measure the
temperature of the nails plus water after about 3
minutes. The nails should be at the same
temperature as the water by this time.
- Heat about 500 cm3
of water to above 80ºC.
- Place a measured
amount (200 cm3 or 300 cm3)
of this hot water an insulated container.
- Measure the
temperature of the water
- Transfer the nails to
the container with hot water.
- Allow the mixture of
water and nails to stand for 3 minutes.
- Measure the
temperature of the mixture.
- The energy lost by
the water in cooling down to the final
temperature will be the energy gained by the
nails in being heated to the final temperature.
Calculations
Calculate the specific
heat capacity of steel as follows:
- Assume that the
specific heat capacity of water is 4180 J / kg.ºC.
- Assume that the
density of water is 1 gram per cm3.
- Using the equation: H
= m x C x D t, calculate the heat lost by
the water. [H is the energy lost( J), m is the
mass of water (kg), C is the specific heat
capacity of water (4180 J / kg.ºC) and D t is
the difference in temperature – the
temperature dropped by the water]
- Using the same
equation, and the value of H calculated above,
substitute a new value of D t.
This is the
temperature difference for the nails – and a
new value for m – the mass of the nails.
- From this, the value
of C for the nails can be determined.
Results
– Experiment 2.7.1
Specific Heat Capacity of Steel
| Volume
of water at used |
|
| Initial
temperature of hot water |
|
| Initial
temperature of nails |
|
| Temperature
of mixture (after 3 minutes) |
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| Temperature
lost by water D t1
= |
|
| Temperature
gained by nails D t2
= |
|
| Energy
lost by water = energy gained by nails = |
|
| Specific
heat capacity of steel = |
|
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