atmosphere and environment Flashcards
1
Q
carbon monoxide
A
- colourless odourless gas
- comes from the incomplete combustion of car engines
- reacts with haemoglobin in blood which reduces the ability of haemoglobin to transport oxygen to the rest of the body
2
Q
sulfur dioxide
A
- fossil fuels such as crude oil, petroleum, natural gas
- burnt in vehicles, power stations and factories
- irritates the eyes and lungs and cause breathing difficulties
- reacts with water and forms acid rain which corrodes buildings (limestones) and harm aquatic life, plants
3
Q
oxides of nitrogen
A
- nitrogen combines with oxygen in the air to form nitrogen monoxide, nitric oxide
4
Q
unburnt hydrocarbons
A
- released in car exhaust fumes and chemical plants
- causes cancer
5
Q
methane
A
- colourless and odourless gas which is produced by plant and animal matter
- greenhouse gas
- causes global warming
6
Q
ozone
A
- formed when nitrogen oxide in the air reacts with unburnt hydrocarbons in the presence of sunlight
- forms photochemical smog, irritates the eyes and lungs, causes breathing difficulties
- damages crops
7
Q
how is acid rain formed?
A
- when acidic air pollutants such as sulfur dioxide and nitrogen dioxide react with water in the atmosphere
- sulfur dioxide dissolves in water to form sulfuorous acid
- in the presence of oxygen in the air it is slowly oxidised to form sulfuric acid
8
Q
what are the effects of acid rain?
A
- reacts with metals and carbonates like marble and limestone, damage buildings
- leaches nutrients from soil and causes them to die
- produce al3 ions which causes plants to die
9
Q
how do catalytic converters help remove pollutants in vehicle exhaust gases
A
- hot exhaust gases pass over the platinum and rhodium catalysts in a catalytic converter
- carbon monixide –> carbon dioxide
- oxides of nitrogen –> nitrogen
- unburnt hydrocarbons –> co2 and water
10
Q
flue gas desulfurisation
A
- cheaper alternative
- as sulfur dioxide passes through a plant it reacts with the suspension of calcium carbonate to form solid calcium sulfite and carbon dioxide gas
- calcium sulfite is further oxidised to from calcium sulfate
- besides calcium carbonate, calcium oxide can also be used
11
Q
what is ozone?
A
pale blue gas with pungent odour, toxic pollutant
12
Q
importance of
ozone layer
A
filters out harmful ultraviolet rays, too much UV can cause skin cancer
13
Q
what causes the depletion of ozone
A
- harmful UV radiation from the sun is absorbed by the protective ozone layer
- propellants like aerosol release CFCs into the atmosphere.
- In the presence of UV radiation CFCs decompose to form chlorine atoms
14
Q
carbon cycle
A
- mechanism that maintains the level of carbon dioxide in the atmosphere
15
Q
how is co2 added into the atmosphere
A
- respiration
- combustion of fuels
- decay and bacterial decomposition
