11.04.8 KEYWORDS

· Sustainable Development – Improving human life without permanently damaging the environment

· Potable Water – water that’s safe to drink

· Fresh Water – water that isn’t salty (maybe unsafe to drink)

· Pure Water – water with nothing dissolved in it.

· Microbes – bacteria, viruses, fungi etc that may cause diseases

· Sterilising Agents – things used to kill microbes in water (Chlorine, Ozone, UV)

· Sewage – waste water that has flown thorough sewers and may contain human waste

· Screening – rough filtering to remove large objects from water

· Sedimentation – leaving water still so that fine solid particles sink

· Effluent – water left over from filtering sewage

· Sewage Sludge – solids filtered out of sewage

· Aerobic Digestion – breaking down sewage waste using microbes in the presence of Oxygen , makes CO₂

· Anaerobic Digestion – breaking down sewage waste using microbes without Oxygen, makes methane

· Desalination – removing salt from sea-water to make drinking water

· Reverse Osmosis – alternative method of desalination to distillation. Uses a semi-permeable membrane

· Semi-permeable membrane – material that allows water through but not salt.

· Soda-lime glass – glass formed from Sand and Sodium Carbonate and Limestone

· Borosilicate Glass – glass made from sand and Born Oxide (can tolerate temperature changes better)

· Ceramics – materials made from clay (tiles, bricks, crockery)

· Thermosoftening polymers – polymers that melt when heated because polymers are not bonded together

· Thermoset Polymers – polymers that don’t melt when heated because polymer chains are bonded together.

· Low density Polymers – polymers where the chains are far apart due to branching

· High density Polymers – polymers with chains close together, little branching

· Composites – materials made of two or more materials, gaining properties from both (eg reinforced concrete contains steel bars)