Flashcards
C2
Flashcards do conjunto (48)
- 1MoleculeGroup of atoms bonded together.
- 2MixtureTwo different substances not chemically joined.
- 3Natural materialsMaterials found in plants and animals, e.g, wood, paper, wool.
- 4Synthetic materialsMan made, e.g, nylon, polyester, rubber.
- 5Advantage of synthetic materialsYou can control its properties.
- 6Raw materials used to make synthetic materials come from...The Earth's crust
- 7Melting pointTemperature where a solid turns to a liquid.
- 8StrengthHow good a material is at resisting a force.
- 9Tensile strengthHow well a material can resist a pulling force.
- 10Compressive strengthHow well a material can resist a pushing force.
- 11StiffnessHow much a material can bend
- 12HardnessHow hard a material is to cut into.
- 13DensityA material's mass per unit volume
- 14Objects that are less dense than water...Float
- 15Objects that are more dense than water...Sink
- 16Uses of a material depend on its...Properties
- 17Properties of plasticsHard
Strong
Stiff
Low density
Mouldable - 18Properties of rubberStrong
Flexible
Mouldable - 19Properties of nylonSoft
Flexible
Good tensile strength - 20Product's properties depend upon...The materials they're made from
- 21Effectiveness of a productHow good it is at its function
- 22DurabilityHow long a product lasts
- 23Crude oilFossil fuel; mixture of hydrocarbons.
- 24Hydrocarbon properties change as...Their chains get longer
- 25Short chain molecules have...Lower boiling points
- 26Long chain molecules have...Higher boiling points
- 27ViscousThick and sticky
- 28Covalent bondsBonds between each atom within a hydrocarbon molecule
- 29Intermolecular forcesForces of attraction between different hydrocarbon molecules in a mixture
- 30Big molecules have higher boiling points because...More energy is needed to break them.
- 31If a molecule overcomes its intermolecular forces...It becomes a gas
- 32Covalent bonds are stronger than...Intermolecular forces
- 33Crude oil is separated by...Fractional distillation
- 34Process of fractional distillation1. Hydrocarbons are separated into groups with different boiling points
2. Hydrocarbons are placed into groups according to their boiling points, called fractions
3. Hydrocarbons with similar boiling points have similar chain lengths; and so similar uses. - 35Chemical synthesisProcess of making new compounds
- 36PolymerisationUnder high pressure, many small small molecules join to form long chains called polymers
- 37Plastics are formed when...Several monomers join to form a polymer
- 38Polymers have replaced...Natural materials in some cases
- 39Advantages of polymers over natural materials...Ligher, more durable, cheaper, water-resistant
- 40Polymer properties depend upon...How the molecules are arranged.
- 41Polymer chains with weak forces...Stretch easily and have a low melting point
- 42Polymer chains with strong forces...Are not as easily stretched and have higher boiling points.
- 43Cross-linksChemical bonds between polymer chains
- 44Polymers can be modified to give them different properties...For example
1. Their chain lengths can be increased to give higher boiling points
2. Polymers can be made stronger by adding cross-links - 45Plasticisers are added...To make a polymer softer
- 46Crystalline structure...Straight chains
- 47NanotechnologyUsing nano particles to modify material properties
- 48Advantages of nano particlesThey have a larger surface area-volume-ratio; giving them different properties
Informações
- Descrição
- FlashCards sobre C2, criado por charliebutler em 14-04-2014.
- Criado por
- charliebutler
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