If you add the valences of each atom in the molecular formula for arsenious acid, H 3 AsO 3, you can see that the molecule, which is uncharged, has a total valence state of 0 (3x(+1) for the hydrogen atoms; 1x(+3) for the arsenic(III) atom; 3x(-2) for the oxygen atoms = 3+3-6 = 0).
Eighty percent of sewage in India is untreated and flows directly into the nation's rivers, polluting the main sources of drinking water, a study by an environment watchdog showed Tuesday.
Therefore, water pollution is any change in water that is harmful to living organisms. Sources of water pollution are divided into two main categories: point source and non-point source. Point source pollution occurs when a pollutant is discharged at a specific source.In other words, the source of the pollutant can be easily identified. Examples of point-source pollution include a leaking pipe or a holding tank with a hole in it, polluted water leaving a factory, or garbage being dumped into a river.These sources of pollution are easy to identify because the cause of the pollution can be observed.n other words, the source of the pollutant can be easily identified. Examples of point-source pollution include a leaking pipe or a holding tank with a hole in it, polluted water leaving a factory, or garbage being dumped into a river.