Saturday, December 5, 2015
Chemical and Particulate Air Pollutants
CHEMICAL AND PARTICULATE AIR POLLUTANTS
By Anton Antonio
December 6, 2015
Talking about air pollution seems simple. The chemical and particulate matters in the atmosphere, however, are a complex concoction of chemical elements. The following are the six most common and basic chemicals elements, in gaseous form, that are in the atmosphere:
CARBON DIOXIDE is a colorless, odorless gas produced by burning carbon and organic compounds and by respiration. It is naturally present in air, about 0.03 percent, and is absorbed by plants in photosynthesis. This is where plants and trees play the biggest role.
SULPHUR OXIDE refers to all sulphur oxides, the two major ones being sulphur dioxide and sulphur trioxide. Sulphur dioxide is a colorless gas with a pungent, irritating odor and taste. It is highly soluble in water forming weakly acidic sulphurous acid. When sulphur dioxide combines with oxygen in the air some sulphur trioxide is slowly formed. Sulphur trioxide rapidly combines with water to produce sulphuric acid. The lifespan of sulphur oxides in the atmosphere is from 4 to 10 days. Sulphur dioxide is used in many industrial processes such as chemical preparation, refining, pulp-making and solvent extraction. Sulphur dioxide is also used in the preparation and preservation of food because it prevents bacterial growth and the browning of fruits.
NITROGEN OXIDE is any of several oxides of nitrogen most of which are produced in combustion and are considered to be atmospheric pollutants such as (1) NITRIC OXIDE – a colorless toxic gas formed in many reactions in which nitric acid is reduced, as in reaction with copper. It reacts immediately with oxygen to form nitrogen dioxide; (2) NITROGEN DIOXIDE – a reddish-brown gas with a pungent and irritating odor. It transforms into the air to form gaseous nitric acid and toxic organic nitrates. It also plays a major role in atmospheric reactions that produce ground-level ozone, a major component of smog. It is a precursor to nitrates, which contribute to increased respirable particle levels in the atmosphere; and, (3) NITROUS OXIDE – a colorless, sweet-smelling, sweet tasting, non-flammable, slightly water-soluble gas that sometimes produces a feeling of exhilaration when inhaled. It is used chiefly as an anaesthetic in dentistry and surgery, in the manufacture of chemicals, and as an aerosol.
VOLATILE ORGANIC COMPOUNDS (or VOCs) are organic chemicals that have a high vapour pressure at ordinary room temperature. Their high vapour pressure results from a low boiling point, which causes large numbers of molecules to evaporate or sublimate from the liquid or solid form of the compound and enter the surrounding air.
SUSPENDED PARTICLES AND DROPLETS could be anything from solid particles and chemical droplets that are suspended in the atmosphere.
RADIOACTIVE SUBSTANCES are considered radioactive because the nucleus of each atom is unstable and give out nuclear radiation in the form of alpha particles, beta particles or gamma rays. Radiation could be detected using a Geiger counter.
It might not be practical to study in detail the origins, formation, constitution and effects of these gaseous-chemical elements as chemists will do. But it is important for us to be at least aware of them in our day-to-day activities as we, somewhere and sometime, will most certainly come across these. At least we will be aware of the fact that they are chemical and particulate air pollutants.
Thoughts to promote positive action…
(Please visit, like and share Pro-EARTH Crusaders on Facebook or follow me at http://antonantonio.blogspot.com/ and http://twitter.com/EarthCrusader/)