水污染 英文版

Sources of water pollution
? The used water of a community is called wastewater, or sewage. If it is not treated before being discharged into waterways, serious pollution is the result.
? Water pollution caused by human activities is a large set of adverse effects upon water bodies such as lakes, rivers, oceans, and groundwater
? Pollutants in water include a wide of chemicals, pathogens 病原体, and physical chemistry or sensory changes.
? The positive ions react with the negative ions in soap to form a scum that clings to clothes and leaves them dingy looking.
Water pollution
? Water pollution is any chemical, physical or biological change in the quality of water that has a harmful effect on any living thing
? The negative ions (anions) are usually sulfate (SO42-), bicarbonate (HCO3-), and chloride (Cl-).
hard water
? Water containing these calcium, magnesium, and iron ions is called hard water.
Water pollution
? Water pollution is the leading worldwide cause of deaths and diseases, and that it accounts for the deaths of more than 14,000 people daily.
and oxygen, life on Earth would be non-existent
? Three fourths of the surface of the Earth is covered with water. Nearly
98% of the water on Earth, though, is seawater-unfit for drinking and not even suitable for most industrial purposes. Something less than 2% of the water is frozen in the polar ice caps, leaving less than 1% available as fresh water.
? Effects of water pollution include poisonous drinking water, poisonous food animals, unbalanced river and lake ecosystems, deforestation and many other effects
Water: Unusual Properties
? Many chemical substances are soluble in water. Thus, they are easily dispersed and eventually are scattered to nearly infinite dilution in the ocean. Those properties of water that make it uniquely suited for the support of life also make it easy to pollute.
Water pollution
Water is Essential for Life
? It covers 71% of the earth's surface and makes up 65 % of our bodies. ? Without the seemingly invaluable compound comprised of hydrogen
Natural Water Isn't All H2O
? Rainwater carries dust particles from the atmosphere to the ground. Rainwater also dissolves a little oxygen, nitrogen, and carbon dioxide as it falls through the atmosphere. During electrical storms, lightning causes nitrogen, oxygen, and water vapor to combine to form nitric acid.
? Awk.baidu.com water moves along or beneath the surface of the Earth, it dissolves minerals and matter from decaying plants and animals.
? The principal positive ions (cations) in natural water are sodium (Na+), potassium (K+), calcium (Ca2+), magnesium (Mg2+), and sometimes iron (Fe2+ or Fe3+).