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Question
You are given a hammer, a battery, a bulb, wires and a switch.
- How could you use them to distinguish between samples of metals and non-metals?
- Assess the usefulness of these tests in distinguishing between metals and non-metals.
Solution
- We can beat the sample with the hammer. If it can be beaten into thin sheets (that is, it is malleable), then it is a metal; otherwise, it is a non-metal. If the bulb glows the sample is metal, a good conductor of electricity. If, on the other hand, the bulb does not glow, the sample is non-metal, a bad conductor of electricity.
- Iron and many other metals are malleable and can be cast into sheets for roofing, trunks, boxes, and storage of articles of daily use. Metals are good conductors of electricity, so copper and aluminium wires are used for carrying electricity. The above tests are useful in distinguishing between metals and non-metals as they are based on their physical properties. No chemical reactions are involved in these tests.
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