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11 Cards in this Set
- Front
- Back
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What are the two different types of materials?
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natural and synthetic
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What do natural materials often come from?
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plant-cotton, wood
animals-wool, silk, leather |
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name 5 properties of materials.
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melting point
strength hardness density |
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whats the difference between tensile and copressive strength.
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Tensile is how much material can resist a puling force compressive is how much amaterial can resist a pushing force.
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what is crude oil a mixture of?
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hydrocarbons
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how are polymers formed?
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small molecules join to give polymers
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If a polymer has weak forces what properties will it have?
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low melting point (the stronger the forces that harer to break up the atoms)and stretch easily (can slide over each other more easily)
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will long or short chain polymers have a low melting point and be easy to shape
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short chain polymers
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whta do plasticisers do to a polymer?
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make it softer and easy to shape, they make bonds weaker.
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A polymer can be made crystalline what are the properties of a crystalline polymer?
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straight close together chainss give it higer density and melting poit and make it stronger.
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What happens to a polymer when you add cross linking agents?
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It chemichally bonds the chains together making the polymer stiffer stronger and more heat resistant.
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