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Acid rain
Indeed natural rain is acidic due to
the dissolved carbondioxide in it
CO2 + H2O ⇌ H2CO3
so the term “acid rain”
is used for rain having a pH
value lower than 5.6
Acid rain is caused by oxides of sulfur and nitrogen
These compounds form sulfuric acid and nitric acid
SO2 + O2 → SO3
SO3 + H2O → H2SO4
2NO2 + H2O → HNO2 + HNO3
3HNO2 → HNO3 + 2NO + H2O
4NO + 3O2 + 2H2O → 4HNO3
NOx emission
a forest destroyed by acid rain
effects of acid rain on historical artifacts
We need to use more of these renewable energy sources
Fresh water
Curently there are more than 6.7 billion people living in this
world and they all need fesh water to survive and acording
to the statistics by the time you have finished reading this
sentence two more babies will be born and we will need
even more fresh water than we did before.
Only 3% of the worlds water is fresh water
3%
And 80% of the
fresh water supply
is in ice caps and
glaciers
Water treatment
Substances that are removed during the process of
drinking water treatment include bacteria, algae, viruses,
fungi, minerals such as iron and sulphur, and man-made
chemical pollutants.
As of 2006, waterborne diseases are estimated to cause
1.8 million deaths each year.
Water treatment is mainly done using chlorine and
it causes death of millions in developing countries