LUCÍA ROMERO
11. AIR AND WATER
11.1 WATER
Uses of water
AT HOME
1. Drinking
2. Cooking
3. Gardening
4. Personal washing
5. Washing clothes
6. Toilet
AT THE FARM
1. For animals to drink
2. For watering crops
IN INDUSTRY
1. As a solvent
2. Irrigation
3. Cooling reactors
4. Make steam to drive a turbine
Purification of water
STAGES
1. There is a sand filter that removes insoluble impurities that are larger than the gaps between the sand molecules (Filtration is the process
used to remove large insoluble particles by passing the water through layers of sand and gravel filters that trap larger particles)
2. The final stage is the addition of chlorine to water to kill the bacteria (Chlorination is used. This involves the careful addition of chlorine to
the water supply which kills bacteria and other unwanted microorganisms)
Physical and chemical tests for water
PHYSICAL:
• Boil the liquid at 100 degrees
CHEMICAL:
1) Anhydrous copper sulphate (white) + water ⇄ Hydrated Copper Sulphate (Blue)
CuSO4 (s) + 5H2O ⇄ CuSO4 5H2O (Blue)
2) Cobalt chloride paper turns from blue to pink when you add water
CoCl2(s) + 6H2O(l) → CoCl2.6H2O(s)
11. 2 AIR
Clean air composition
→ 78% NITROGEN
→ 21% OXYGEN
→ 1% MADE UP OF: noble gases (argon) and carbon dioxide
, LUCÍA ROMERO
Separating the mixture
The gases can be separated by fractional distillation
STAGES
1. First the air is cooled down until it becomes a liquid.
2. Then it is warmed up slowly. This allows the gases to boil off separately, since they all have different boiling points.
3. The gases are put into tanks or cylinders under pressure and sold for different uses.
Uses of oxygen and nitrogen
The pollutants
POLLUTANT SOURCE HARMFUL EFFECT
1. Carbon monoxide CO Incomplete combustion, when fields are It is deadly, as it stops the hemoglobin from
burnt with a limited supply of oxygen carrying oxygen, therefore dying from
2C + O2 → 2CO oxygen starvation
2. Carbon particulates Particles in air are either: directly emitted, They are black or dark particles of carbon
for instance when fuel is burnt and when that turn buildings black
dust is carried by wind, or:
indirectly formed, when gaseous pollutants
previously emitted to air turn
into particulate matter.
3. Sulfur dioxide SO2 Sulfur is an impurity found in coal, so when 1. It causes lung damage
coal is burnt, sulfur is released, and it 2. Breathing problems
reacts with oxygen. (from fossil fuels) 3. Form acid rain, damges crops, buildings
and kills fish
4. Nitrogen oxides NO (not acidic), NO2 1. Reaction of nitrogen with oxygen in car 1. Acid rain as producing
(acidic) engines at high pressure and temperature 2. Smog
2. High-temperature furnaces 3. Breathing difficulties, asthma
3. As a product of bacterial action in soil
5. Lead compounds 1. Old water pipes 1. causes significant damage to the central
2. Old paints nervous system
3. Petrol in some kinds of racing cars and 2. Can cause brain damage
4. Very old engines 3. Behavioral problems
6. Carbon dioxide CO2 Combustion of fuels that contain carbon Climate change, greenhouse effect
Catalytic converters and nitrogen oxides
Catalytic converters → A device that oxidizes and reduces exhaust gases by using catalysts
→ The metal catalysts (usually transition metals) are in a honeycomb within the converter to increase the surface area
available for reaction
11. AIR AND WATER
11.1 WATER
Uses of water
AT HOME
1. Drinking
2. Cooking
3. Gardening
4. Personal washing
5. Washing clothes
6. Toilet
AT THE FARM
1. For animals to drink
2. For watering crops
IN INDUSTRY
1. As a solvent
2. Irrigation
3. Cooling reactors
4. Make steam to drive a turbine
Purification of water
STAGES
1. There is a sand filter that removes insoluble impurities that are larger than the gaps between the sand molecules (Filtration is the process
used to remove large insoluble particles by passing the water through layers of sand and gravel filters that trap larger particles)
2. The final stage is the addition of chlorine to water to kill the bacteria (Chlorination is used. This involves the careful addition of chlorine to
the water supply which kills bacteria and other unwanted microorganisms)
Physical and chemical tests for water
PHYSICAL:
• Boil the liquid at 100 degrees
CHEMICAL:
1) Anhydrous copper sulphate (white) + water ⇄ Hydrated Copper Sulphate (Blue)
CuSO4 (s) + 5H2O ⇄ CuSO4 5H2O (Blue)
2) Cobalt chloride paper turns from blue to pink when you add water
CoCl2(s) + 6H2O(l) → CoCl2.6H2O(s)
11. 2 AIR
Clean air composition
→ 78% NITROGEN
→ 21% OXYGEN
→ 1% MADE UP OF: noble gases (argon) and carbon dioxide
, LUCÍA ROMERO
Separating the mixture
The gases can be separated by fractional distillation
STAGES
1. First the air is cooled down until it becomes a liquid.
2. Then it is warmed up slowly. This allows the gases to boil off separately, since they all have different boiling points.
3. The gases are put into tanks or cylinders under pressure and sold for different uses.
Uses of oxygen and nitrogen
The pollutants
POLLUTANT SOURCE HARMFUL EFFECT
1. Carbon monoxide CO Incomplete combustion, when fields are It is deadly, as it stops the hemoglobin from
burnt with a limited supply of oxygen carrying oxygen, therefore dying from
2C + O2 → 2CO oxygen starvation
2. Carbon particulates Particles in air are either: directly emitted, They are black or dark particles of carbon
for instance when fuel is burnt and when that turn buildings black
dust is carried by wind, or:
indirectly formed, when gaseous pollutants
previously emitted to air turn
into particulate matter.
3. Sulfur dioxide SO2 Sulfur is an impurity found in coal, so when 1. It causes lung damage
coal is burnt, sulfur is released, and it 2. Breathing problems
reacts with oxygen. (from fossil fuels) 3. Form acid rain, damges crops, buildings
and kills fish
4. Nitrogen oxides NO (not acidic), NO2 1. Reaction of nitrogen with oxygen in car 1. Acid rain as producing
(acidic) engines at high pressure and temperature 2. Smog
2. High-temperature furnaces 3. Breathing difficulties, asthma
3. As a product of bacterial action in soil
5. Lead compounds 1. Old water pipes 1. causes significant damage to the central
2. Old paints nervous system
3. Petrol in some kinds of racing cars and 2. Can cause brain damage
4. Very old engines 3. Behavioral problems
6. Carbon dioxide CO2 Combustion of fuels that contain carbon Climate change, greenhouse effect
Catalytic converters and nitrogen oxides
Catalytic converters → A device that oxidizes and reduces exhaust gases by using catalysts
→ The metal catalysts (usually transition metals) are in a honeycomb within the converter to increase the surface area
available for reaction
