Using Resourses Flashcards
What is potable water?
- Water that is safe to drink
- It contains dissolved impurities (it is not pure)
What is ground water?
Water that is stored in permeable rock underground.
What are the two stages of water treatment?
- Filtering
- Sterilizing (to kill harmful microbes in the water)
What three things can be used to sterilize water?
- Chlorine
- Ozone
- UV light
What are the two methods of desalination?
- Distillation
- Reverse osmosis
How does reverse osmosis work?
Salty water is forced through a very fine filter by pressure. The water molecules pass through, but the dissolved salts are trapped by the filter.
What does sewage contain?
- Organic matter
- Harmful microbes
- Pesticides and fertilizers
- Harmful chemicals
What is the first stage of sewage treatment?
- Screening
- A metal grid is used to separate and remove solid objects and grit
What is the second stage of sewage treatment?
- Sludge settles at the bottom of the tank and is separated
- Effluent flows to the next tank
What is the third stage of sewage treatment?
- Bacteria break down organic matter and microbes aerobically
What is the final stage of sewage treatment?
- Useful bacteria settle at the bottom of the tank and are recycled
- Water is released to the environment
What is phytomining?
Extracting copper form low grade copper sites.
Planting plants on low grade copper sites, allowing the plants to grow and absorb copper compounds, then burning the plants into ash containing these compounds.
What is bioleaching?
Extracting copper form low grade copper sites.
Flooding low grade copper sites with bacteria, allowing the bacteria to absorb copper, then passing liquid through the large colony of bacteria to produce a leachate solution containing the compounds.
How do you extract copper from a solution of copper compounds?
- Displacement with scrap iron
- Then electrolysis to get pure copper
What is ash dissolved in before the copper is extracted?
Dissolve the ash in sulfuric acid.
What is rust?
- The breakdown of iron by its reaction with water and oxygen.
- Forms hydrated iron oxide.
What is corrosion?
The breakdown of non-iron metals by chemical reactions that they are exposed to.
What are the 5 methods of preventing rust?
- Painting
- Plastic coating
- Covering in oil
- Galvanizing
- Mixing with other elements (alloy)
Why does sacrificial protection work even if there are gaps in the coating?
There is still more reactive metal nearby so the oxygen will react in preference with this metal.
What is used for sacrificial protection for steel?
Zinc
What are the components of brass?
- Copper
- Zinc
What are the components of bronze?
- Copper
- Tin
What are the components of high carbon steel and low carbon steel?
- Iron
- Carbon
What are the components of gold (18 carat)?
- Gold
- Silver
- Copper
- Zinc
What are the components of stainless steel?
- Iron
- Carbon
- Chromium
- Nickel
What are the property of gold?
- Very malleable
- Doesn’t oxidize
- Shiny
What are the property of high carbon steel?
- Hard
- Brittle
- Can be sharpened
What are the property of low carbon steel?
- Malleable
- Strong
- Thin layer are lightweight
What are the property of stainless steel?
- Does not oxidize
How do you calculate the % of gold in a sample?
Divide the carat number by 24.
What is the structure of LDPE?
- Low density
- Branched chains (prevent tight packing)
- Weak structure
- Low melting point
What is the structure of HDPE?
- High density
- Strait chains (allow tight packing)
- Strong structure
- High melting point
What is the structure of thermosetting polymer chains?
Rigid structure with fixed chains.
What is the structure of thermosoftening polymers chains?
Long strait chains that are tangled.
How is LDPE formed?
- High pressure
- Trace oxygen
How is HDPE formed?
- Low pressure
- Catalyst
- 50°C
What is the structure and bonding of LDPE?
Weak intermolecular forces.
What is the structure and bonding of HDPE?
Strong intermolecular forces.
What is the structure and bonding of Thermosoftening polymers?
Weak intermolecular forces - easily broken with heat.
What is the structure and bonding of Thermosetting polymers?
Strong covalent bonds, with bonds linking chains together (cross links), don’t break when heated.
Why is clay slippery when wet?
Water molecules sit between layers of clay.
What is the structure of set clay?
Giant covlent.
What type of glass is the most commen?
Sodalime glass.
What are the components of sodalime glass?
- Sand
- Sodium
- Limestone
Which type of glass can be heated without melting?
Borosilicate glass.
What are the components of borosilicate glass?
- Sand
- Boron trioxide
What is the name for the main component of a composite?
A matrix.
What does the Haber process produce?
Ammonia.
What are the reactants for the Haber process?
Nitrogen (from the air) and hydrogen (from natural gas).
What temperature and pressure is used for the Haber process?
450°C and 200 atmospheres.
What is the catalyst for the Haber process?
Iron.