#151 Air Pollution Past Times Sulfur Dioxide (So2), Acid Pelting

SO₂ released into the air when coal in addition to oil are burned. Power stations cease large amounts of these fossil fuels. SO₂ dissolves inward the H2O vapour inward clouds, forming sulphuric acid (H₂SO₄₎. When it rains, the rain is acidic.

The combustion of petrol inward automobile engines too contributes to acid rain, only this is mainly due to the production of oxides of nitrogen inward the exhaust fumes, rather than SO_2.

Acid rain

The primary causes of acid pelting are procedure that release SO₂ and oxides of nitrogen into the atmosphere. These include:

• burning of fossil fuels, such equally coal in addition to gas, yesteryear mightiness stations
• combustion of petrol inward car engines.

Problems caused yesteryear acid pelting include:

• Damage to plant leaves, eventually killing the plants. Whole forests of pino trees own got been destroyed yesteryear acid rain.

Plant leaves damaged yesteryear acid rain. 

• Acidification of lakes: equally the H2O teach to a greater extent than acidic, around animals such equally fish cannot hold upwards in addition to fish stocks are destroyed.
• Increased lead chances of asthma attacks and bronchitis inward humans.
• Corrosion of stonework on buildings.
• Release into reason of soluble aluminium ions that are toxic to fish when washed into lakes.

Ways of reducing the incidence of acid rain:

• changing the types of mightiness stations that generate electricity from coal in addition to crude to gas or nuclear power, or using to a greater extent than renewable issue energy sources such equally wind
• using ‘scrubbers’ inward mightiness station chimneys – these withdraw almost of the SO₂ present inward the waste product gases
• using catalytic converters inward automobile exhausts – these convert oxides of nitrogen to harmless nitrogen.

Common misconceptions

Remember that automobile engines do not  make large total of SO₂ – only they are responsible for producing large total of oxides of nitrogen, CO₂ and CO.

Examiner’s tip

When describing the effects of automobile exhaust fumes on the environment, don’t brand a listing of the chemicals in addition to and therefore link them all to acid pelting or global warming. Be specific:

• oxides of nitrogen leas to acid rain;
• CO tin trim the mightiness of haemoglobin to behaviour O₂;
• CO₂ increases tin atomic number 82 to global warming.

Try this

1. SO₂ is a major  pollutant of the air. Which procedure is mainly responsible for the issue of SO₂ into the air?                                                       [1 mark]

2. SO₂ is i of the gases which contributes to acid rain. Acid pelting tin touching on trees in addition to their surrounding reason inward a diversity of ways. Figure below shows where these effects tin occur.

Suggest how each of the next affects the tree in addition to explicate how it tin atomic number 82 to its death.

i) Damage of the leaves                                                       [2 marks]

ii) Damage of the fine roots                                                 [2 marks]

iii) Death of the reason microorganisms                                   [2 marks]

Answer

1. Combustion of fossil fuels.

2. i) The leaves are unable to photosynthesise, therefore it cannot brand food.

ii) One suggestion in addition to explanation from:

- the roots are unable to absorb water, therefore cells volition teach flaccid, or the tree volition wilt, or carry of materials volition non happen

- the roots are unable to absorb mineral salts which are needed, e.g. for formation of chlorophyll, or for growth. 

iii) One proposition in addition to explanation from:

- less decomposition volition occur, therefore at that topographic point volition live less minerals available to the plant, e.g. magnesium ions for formation of chlorophyll.

- at that topographic point volition live no nitrogen-fixing bacteria, therefore at that topographic point volition live less nitrates for the roots to accept up, which are needed for poly peptide formation.