One of the unusual properties of metals is their high heat conduction. This means that, when heated, their temperature goes up faster than than of many other materials. You can show this simply by placing spoons or forks made of metal and other materials into hot water.What You'll Need:
Microwave-safe mug
Water
Several spoons or forks, made of different materials such as metal, wood, or plastic
Microwave oven
Potholder
Fill the mug with water and microwave it for three minutes. Using the potholder, remove the mug from the oven, and place the spoons or forks in the water. Make sure that they don't touch one another. Carefully touch each spoon or fork over the next few minutes. Which one gets hot fastest? Which one stays cool longest?
You'll find that the metal definitely heats up first. This happens because the atoms in the metal absorb energy from the hot water and begin to move faster. Faster-moving atoms are hotter atoms. Other materials, such as wood or plastic, are insulators, and their atoms resist taking on more energy. So, they stay cooler!
Here's another heat conduction experiment that you've done hundreds of times, probably without realizing that it's an experiment! Touch something made of metal that has been just sitting in the room. Does it feel hot or cold? Metals feel cold to the touch, but does this mean that they are at a lower temperature than your hand? Unless you just took the metal out of the fridge, it's at the same temperature as everything else in the room! So, how can it feel cold? The metal is now absorbing heat from your hand, just like it did from the hot water in the experiment above. Your hand senses that you are losing heat, and your brain then thinks that the metal must be cold - but you're just fooling yourself!
Microwave-safe mug
Water
Several spoons or forks, made of different materials such as metal, wood, or plastic
Microwave oven
Potholder
Fill the mug with water and microwave it for three minutes. Using the potholder, remove the mug from the oven, and place the spoons or forks in the water. Make sure that they don't touch one another. Carefully touch each spoon or fork over the next few minutes. Which one gets hot fastest? Which one stays cool longest?
You'll find that the metal definitely heats up first. This happens because the atoms in the metal absorb energy from the hot water and begin to move faster. Faster-moving atoms are hotter atoms. Other materials, such as wood or plastic, are insulators, and their atoms resist taking on more energy. So, they stay cooler!
Here's another heat conduction experiment that you've done hundreds of times, probably without realizing that it's an experiment! Touch something made of metal that has been just sitting in the room. Does it feel hot or cold? Metals feel cold to the touch, but does this mean that they are at a lower temperature than your hand? Unless you just took the metal out of the fridge, it's at the same temperature as everything else in the room! So, how can it feel cold? The metal is now absorbing heat from your hand, just like it did from the hot water in the experiment above. Your hand senses that you are losing heat, and your brain then thinks that the metal must be cold - but you're just fooling yourself!
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