CHEMISTRY - TOPIC 10 - USING RESOURCES

do thermosetting or thermosoftening polymers melt easily when heated

thermosoftening - weak intermolecular forces break easily

are metals or alloys malleable

metals

what two components are needed for rusting

water

oxygen

what is meant by galvanising

coating an object in zinc

what is corrosion

the slow breaking down of a metal cause by reacting with substances in their environment

what us the purpose of a life cycle assessment (LSA)

to asses the environmental impact of products

how do we make our fresh water safe to drink?

step 1: filter it through a mesh wire

step 2: run water through a bed of sand and rock to filter out any sediment

step 3: sterilise it to remove/kill any bacteria

what is desalination

getting potable water from sea water

why is desalination not very reliable

the processes that can be used cam be very expensive as they use lots of energy

what are the three criteria for potable water

1)pH level must be between 6.5-8.5

2)must not contain any microorganisms( bacteria/ fungi)

3)amounts of dissolved substances must be fairly low

what are the three categories of waste called

domestic

agricultural

industrial

what are the three essential elements needed for fertilisers

phosphorus

potassium

nitrogen

how does ammonia make nitric acid

ammonia reacts with oxygen and water

how does ammonia make ammonium salts

ammonia reacts with acids to form the salts

what is meant by a formulation

a mixture designed as a useful product