Environmental chemistry deals with the study of the origin, transport, reactions, effects, fates of chemical species in the environment.
ENVIRONMENTAL POLLUTION:- Environmental pollution is the effect of undesirable changes in our surroundings that have harmful effects on plants, animals and human beings. A substance which causes pollution is called a pollutant. they can be solid, liquid or in the gaseous state.
ATMOSPHERIC POLLUTION:- The atmosphere that surrounds the earth is not of the same thickness at different heights. Atmospheric pollution is generally studied as tropospheric and stratospheric pollution. The ozone layer prevents about 99.5 % of the sun’ s UV rays.
TROPOSPHERIC POLLUTION:- Tropospheric pollution occurs due to the presence of undesirable solid or gaseous particles in the air. The following are the major gaseous and particulate pollutants present in the troposphere;
� Gaseous air pollutants: These are oxides of sulphur, nitrogen and carbon, hydrogen sulphide, hydrocarbons, ozone and other oxidants. � Particulate pollutants; these are dust, mist, fumes, smoke, smog etc
GLOBAL WARMING AND GREENHOUSE EFFECT:- About 75 % of the solar energy reaching the earth is absorbed by the earth’ s surface, which increases it’ s temperature. The rest of the heat radiates back to the atmosphere. Some of the heat is trapped by the gases such as carbon dioxide, methane, ozone, CFCS and Water vapour. they add to the heating of the atmosphere causing Global warming
In a greenhouse, visible light passes through the transparent glass and heats up the soil and the plants. The warm soil and plants emit infrared rays, it partly reflects and partly absorbs these radiations, this mechanism keeps the energy of the sun trapped in the greenhouse.