10. using resources

hard, brittle, heat resistant, corrosion resistant

brick, china, porcelain they have high compressive strength

shaping wet clay while its soft heating it at high temperature in a furnace to harden

transparent, strong and a good thermal insulator

melting a mixture of sand (silicon oxide), sodium carbonate and limestone, then allowing the molten liquid to cool and solidify

heat sand with boron trioxide higher mp than soda lime glass

a material that consists of 2 or more materials with different properties, that have been combined to produce a material with more desirable properties

the reinforcement - often long solid fibres or fragments the matrix - which binds the reinforcements together, usually starts soft than hardens

large molecules of relative high molecular mass and are made by linking together monomers flexible, easily shapes and good insulators of heat and electricity

low density poly(ethene) = LDPE density poly(ethene) = HDPE

C. moderate temps, high pressure, catalyst P. more flexible but weaker U. carrier bags

C. low temps / pressure, catalyst P. more rigid but stronger U. drainpipes

made from lots of polymer chains, held together by strong covalent bonds. Require lots of energy to break, dont soften when heated. hard, strong, rigid

made from lots of polymer chains, held by weak intermolecular forces break easily when heated= polymer melts= can be remoulded into shapes and will harden when cooled

the process by which metals are slowly broken down by reacting with substances in their environment

rusting = redox iron + oxygen + water –> hydrated iron (iii) oxide Fe –> Fe^3+ + 3e- (oxidised) 02 + 4e- –> 20^2- (reduced)

water, oxygen = present

adding a more reactive metal to the iron: e.g aluminium or zinc if the object is exposed to 02 the more reactive metal will be oxidised instead

GALVANISING coating the object in a layer of zinc=barrier if zinc is scratched it will react with any o2 as = more reactive

an approach to human and economic development that meets the needs of present generations, without compromising the ability of future gens to meet their needs

use renewable resources: make objects from wood not plastic, can grow more trees instead of using crude oil = finite

reuse - lengthen an items life for the same or different purpose recycle- collecting and processing material that would be thrown away, and turning them into new products

only the surface metal as its exposed to substances in the environment

if iron is left long enough the entire chunk can break down as new layers become exposed in aluminium only the surface atoms are affected to = aluminium oxide which forms a protective layer