Using Resources Materials Continued (unit 10) Flashcards
What is the structure and bonding of a pure metal? Please also mention it’s properties
1) GIANT LATTICE
2) Crystalline structure (organised in regular layers)
3) Lattice of + ions HELD TOGETHER WITH DELOCALISED ELECTRONS
4) Consists of metallic bond
Properties: malleable, softer
What is an alloy?
Substance consisting of one metal MIXED with another metal/carbon usually
What is the structure and bonding of alloys? Please also mention properties
1) Has he same metallic bonds
2) ATOMS OF DIFFERENT ELEMENTS DISRUPT THE REGULAR LAYERS DUE TO THE DIFFERENT PARTICLE SIZE
3) It has the mixed properties of big metals when they were separate
Properties: Stronger, harder
Give the composition, properties, and uses of the alloy BRONZE.
- Copper and tin
- Tough and resistant to corrosion
- Used for statues and decorative objects;coins
Give the composition, properties, and uses of the alloy BRASS.
- Copper and zinc
- Harder than copper but is can be worked into intricate shapes
- Used in musical instruments;door handles as copper has ANTIBACTERIAL PROPERTIES
Give the properties, and uses of the alloys of ALUMINIUM.
- LOW DENSITY, though, it is very strong
- Aerospace engineering + aircrafts
Give the composition, properties, and uses of the alloys of GOLD.
- Gold + silver/copper/zinc
- This changes the hardness and colour
- used for jewellery
His is the purity of gold calculated?
x carats/24 carats
24 is 100% pure
Give the composition, properties, and uses of the alloys of STEEL.
- Iron alloys that contain carbon and other metals
- Used in infrastructure e.g. railways, bridges, skyscrapers, (stainless steel) cutlery
What are the three types of steel and/or composition?
High carbon steel
Low carbon steel
Stainless steel (iron and carbon and chromium and nickel)
What is property of high carbon steel?
It is strong
It is less corrosive
It is brittle
What is the property of low carbon steel?
Softer
More easily shaped
It is MORE corrosive
What are the properties of stainless steel?
Hard
Corrosion RESISTANT
Shinier
What is the property of glass compared to ceramics?
Transparent v. Opaque
What are uses of ceramics?
Bricks, toilets, crockery
What is ‘soda-lime glass’ glass made out of?
Sand/silicon dioxide + sodium carbonate + limestone
How do I get glass that’s harder and has higher temperature?
Melt at high temperature and shape when cooling
What is the name of the harder and higher MELTING point glass?
Borosilicate glass
What are the uses of the higher MELTING point and harder glass?
Test tubes
What is the structure of glass like?
Irregular structure
What are ceramics made from?
Clay
How are ceramics made?
They are heated to a high temperature in a furnace and moulded into shape when wet
What is the structure of clay and of ceramics?
Clay: mixture of compounds containing both ionic and covalent bonds
Ceramics: Regular, CRYSTALLINE structure
What are the properties of ceramics?
It is hard
It is brittle so can easily crack
It’s an insulator
It is corrosion resistant
What are composite materials?
Give an example of one
2 or more materials binded together (using binder or matrix surrounding and binding together fibres of other material which is called REINFORCEMENT) that provide improved properties that neither material could provide separately
E.G. concrete
What is the structure and uses of fibreglass?
Boats and sports equipment
The binder/second material is a POLYMER
Tough but flexible, waterproof, low density
What is the structure and uses of concrete?
Cement and water
Used for buildings
What are the uses of glass-ceramics?
Structure?
Stoves
Both individually are hard but brittle; together they are hard but TOUGH
What is the structure and uses of composite wood?
Plywood and MDF
Binder is adhesives; sheets of wood stuck together against grain
Used for furniture as shapes can be cut without splintering
How can we change the properties of monomers?
1) Can change the monomers used to make the polymer
2) Change the conditions used in the polymerisation reaction
What is example of a polymer that has been made from the same monomer with different reaction conditions?
Low Density Poly(ethene) and High Density Poly(ethene)
Properties/structural differences between LD Poly(ethene) and HD Poly(ethene)?
LD poly(ethene): soft and flexible HD poly(ethene): hard and strong There are stronger forces between the molecules
How are the reaction conditions for HD poly(ethene): compared to LD poly(ethene)?
HD poly(ethene) is made with a LOWER temperature and pressure and the catalyst is Ziegla-Natta but with LD Poly(ethene) the catalyst is traces of oxygen
Uses of LD poly(ethene) and HD poly(ethene)?
LDP: bags + cling film
HDP: buckets and water pipes
What is the STRUCTURE of thermosetting polymers compared to thermosoftening?
Thermosoftening: contains long polymer chains and are tangled with each other
Thermosetting: same as thermosoftening but the chains are JOINED TOGETHER BY COVALENT BONDS (called cross-links)
What are the PROPERTIES of thermosoftening polymers?
Soften and melt when heated
What are the PROPERTIES of thermosetting plastics?
Do not soften and melt when heated (heat resistant)
Examples of thermosoftening polymers?
Poly(ethene)
Polyesters
Nylon
Examples of thermosetting plastics?
Superglue
Epoxy resins
Melamine
Why are aluminium alloys expensive?
A lot of energy to extract aluminium via electrolysis.
What is the ore for iron?
Hematite
Define matrix
Surrounds reinforcement
Fine material used to bind together the coarser particles of a composite substance.
