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the properties of materials. Why is a pan made of metal, but its handle is made of plastic or wood?

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Read and think. One, read and find out. A, three basic ways materials can be classified.

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B, an example of each. Different materials have different properties. They can be classified by

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physical properties, solubility, and by thermal conductivity. Physical properties, hard or soft.

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Hard materials are very difficult to scratch or cut easily. Soft materials are scratched or cut

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easily. A diamond is a hard material. Chalk is a soft material. Tough or fragile. Tough materials

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are very difficult to break. Fragile materials break easily. Steel is a tough material, right,

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because it's a really, really thick metal. Glass is a fragile material. We know that because if

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we drop a glass, what happens? It breaks. Plastic or elastic. Plastic materials are easy to bend.

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And elastic materials go back to their shape after we squash or stretch them.

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Polythene is a plastic material.

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Sponge is an elastic material.

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Right?

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Because you can squish a sponge and then it goes back to its original shape after you squish it.

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Solubility.

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Solubility describes if a material can dissolve in water.

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Materials that dissolve are soluble.

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Materials that don't dissolve are insoluble.

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When you put salt in water and stir, so if you put salt in water and you stir, the salt dissolves.

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The salt is thus soluble.

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When you put pepper in water and stir, the pepper doesn't dissolve.

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Pepper is thus insoluble.

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Thermoconductivity. Thermoconductivity describes if a material can get very hot. Materials that can get hot are thermal conductors. Materials that don't get hot are thermal insulators, because they insulate the heat, meaning they keep the heat as opposed to conduct it or release it.

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metal is a thermal conductor plastic and wood are thermal insulators the metal gets very hot

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so you can iron your clothes the plastic doesn't get hot so you can hold the iron right so it goes

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back to the question is why is a pan made of metal but its handle is made of plastic or wood

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because you couldn't hold the metal if you didn't have plastic or wood because you would burn

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yourself because it's a thermal conductor. Pans are made of metal so that

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they can get very hot and cook food. Spatulas are made of wood or plastic so

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they don't get hot and you can hold them.