C10 Flashcards
What do humans ues the earth resources?
warmth, shelter, food
and transport.
Natural resources are supplemented by algriculture to provide….
food,
timber, clothing and fuels.
WHta are the finite resoucrs form the earth processed to provide?
energy and materials
What is the importance of Chemistry in life?
- improving agricultural and
industrial processes to provide new products - sustainable
development
Define sustanible development
development that meets the needs of current
generations without compromising the ability of future generations
State examples of natural products that are supplemented or
replaced by agricultural and synthetic products
-Natural firtiliser ( maure)
-Rubber
What does dinking water nedd sufficently low levels of ?
dissolved salts
and microbes( bacteria)
Water that is safe to drink is called…
potable water
Is potable water chemically pure? Explain
Potable water is not pure water in the chemical sense because it
contains dissolved substances.
What do methods to produce poatble water depend on?
available
supplies of water and local conditions ( access to sea ect)
Whta type of water is rainwater?
Fresh water
How is poatble water prodced in the UK?
- choosing an appropriate source of fresh water
- passing the water through filter beds
- sterilising.
What are the sterlising agents used for poatable water?
chlorine, ozone or
ultraviolet light.
Define fresh water
water with low levels of
dissolved substances
Rain water collects in what 3 places
ground and in
lakes and rivers
If supplys of freshwater are low…
desalination of salty water or
sea water may be required
What re the 2 methods of desalination ? How much energy do theses processes require?
1.distillation
2. processes that use membranes such as reverse osmosis-> put saltwater through partially permiable membrane and the salt dosn’t pass through
=>processes require large amounts of energy
Analysis and purification o f water samples from different sources. To include pH measurement,
removal of dissolved solids and distillation.
- Use universal indicator to test the pH of the water.
- Measure and record the mass of an empty evaporating basin.
- Pour 10 cm3
water into the evaporating basin and evaporate the water using a
bunsen burner until the most of the water has evaporated. - Once the evaporating basin is cool, reweigh and record the change in mass.
- Calculate the mass of dissolved solids in the water.
RQ: Anlysisng and purifying water samples
How would you tell the pH of a water sample
Add Universal indicator
What 2 prosess produce larged amounts of waste water
Urban lifestyles and industrial processes
Sewage and agricultural waste water require removal
of…….
organic matter and harmful microbes
Industrial waste water may
require removal of…..
organic matter and harmful chemicals
Are the Earth metal ores limited?
YES
What ore is becomeing scarce?
Copper