Quick Lab
Comparing Heat Conductors
Materials
2 plastic foam cups, scissors, metric ruler, metal rod, wooden rod, 2 liquid crystal thermometers, hot water, clock or watch with second hand
Procedure 
Make a data table with a column for time and a column to record the temperature of each rod.
Cut 3 cm off the top of one cup. Turn the cup upside down. Use the metal rod to make two holes about 3 cm apart in the bottom.
Attach a thermometer to each rod as shown.
Insert both rods so they will just touch the bottom of the second cup. Lay the cup with the rods on the table. Do not touch the rods and thermometers during the experiment.
Ask your teacher to add hot water to the intact cup until it is about three fourths full.
Hold the cup with the hot water firmly as you place the cup with the rods on top of it. CAUTION Be careful not to overturn the cup.
Observe and record the temperatures every minute for five minutes.
Analyze and Conclude
Comparing and Contrasting Is metal or wood a better conductor of heat? Explain.
Applying Concepts Is a metal cup a good container for keeping a drink hot for as long as possible? Give a reason for your answer.
Evaluating Describe any variables, other than the type of material, that were not controlled in this lab.
Figure 10 Because gold is both malleable and beautiful, it is often used to make jewelry. These ancient gold medallions were made to form a necklace.
Conductivity
Which spoon should yo choose for stirring a pot of soup heating on the stove—a metal spoon or a wooden spoon? If one end of a metal object is heated, the other end will soon feel hot. A material's ability to allow heat to flow is called conductivity.
Materials that have a high conductivity, such as metals, are called conductors. If a material is a good conductor of heat, it is usually also a good conductor of electricity. Wood is not a good conductor of heat. Yo can stir hot soup with a wooden spoon without worrying about burning your hand because the wooden spoon stays cool to the touch.
Malleability
The ancient gold objects in Figure 10 were found in a tomb in Greece. A goldsmith made the medallions by tapping gold with a small hammer and punch. Gold can be shaped in this way because it is malleable. Malleability (mal ee uh bil uh tee) is the ability of a solid to be hammered without shattering. Most metals are malleable. By contrast, an ice cube breaks into small pieces when struck with a hammer. So does ordinary glass when hit by a fast-moving object such as a baseball. Solids that shatter when struck are brittle.
Why would a cook use a wooden spoon to stir hot soup?
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