C11 Air and Water Flashcards
(30 cards)
Describe the chemical test for water using cobalt (ll) chloride
Blue anhydrous cobalt chloride turns pink in the presence of water
Describe the chemical test for water using copper sulfate
White anhydrous copper sulfate turns blue in the presence of water
What does potable mean
Safe to drink
What two main stages are required to make water potable?
Filtration: removes insoluble particles by passing the water through layers of sand and filter
Chlorination: kills bacteria and microorganisms which are too small to be removed by filtration
How is water used in home
Drinking cooking plumbing heating dishwasher
How is water used in industry
Solvent, coolant, cleaning
Composition of gases in the atmosphere
78% nitrogen
21% oxygen
0.93% argon
0.04% co2
Common pollutants in air
Carbon monoxide
Sulfur dioxide
Oxides of njtrogen
Lead compounds
Sources of pollutants
Carbon monoxide: incomplete combustion of carbon containing compounds.
Sulfur dioxide: combustion of fossil fuels which contain sulfur
Oxides of nitrogen: car engines
Lead engines: leaded petrol
What is catalytic converter?
They are fitted in cars to remove oxides of nitrogen. They catalyse reaction between carbon monoxide and nitrogen monoxide, forming nirogen and co2
Word equation of the reaction that takes place in a catalytic converter
Carbon monoxide+nitogen monoxide>carbon dioxide+nitrogen
What are the problems associated with carbon monoxide
Its a toxic gas.
Odorless and colorless and uf breathed in it can cause DEATH by preventing the rbc from carrying oxygen around the body
Problems associated with sulfur dioxide
It combines with water vapour in the clouds to form acid rain. Acid rain causes the following problems:
-corrodes limestone buildings and statues
-lowers pH of large bodies of water, killing the wildlife
-damages and kills vegetation
Problems associated with oxides of nitrogen
-produces acid rain with simialr effect as So2
-reacts with other pollutants to form a smog which causes respiratory problems
Why is pollution a global concern?
Fossil fuels are used globally and so these pollutants are largely found all over the world. Pollution enters the atmosphere where it affects all countries, not just those that use fossil fuels heavily
What is rusting
Name specifically given to the corrosion of iron where it reacts to oxygen and water in the air
Which two substances need to be excluded to prevent rusting
Oxygen and water
How can oxygen and water be excluded to prevent iron rusting
-paint the metal
-coat the metal in oil
-cover metal in plastic
-keep the metal in vaccum container
What is sacrificial protection? How does it prevent corrosion?
Sacrificial protection involves coating the metal being protected with a more reactive metal. The outer metal will corrode first and will prevnt it
Link the reactivity series to the metals used in sacrificial protection
The metal used for protection must be higher up the reactivity series than the other metal so that it is more reactive. This means it will corrode first.
What is galvanization
The sacrificial protection of iron using zinc
Compounds of which three elements wre commonly found in fertilisers
Nitrogen, phosphorus and potassium cuz it improves agricultural production. They’re absorbed by plants roots to help growth and development
How can ammonia be produced from an ammonium salt byva displacement reaction
When ammonium salt is reacted with a strong base, ammonia us produced along with water and a differeng salt
Harber process
An industrial process used ro produce ammonia for fertilisers
