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.
Water pollution in India is far more deadly but the authorities are yet to acknowledge the magnitude of the crisis, former Union Environment Minister Jairam Ramesh on Tuesday said. Referring to the smog crisis in the national capital, Ramesh rued that the country wakes up to air pollution only when Delhi gets affected.