Water
Water is a compound that is composed of hydrogen and oxygen. It is estimated that about 70% of the surface of the Earth is covered with water. This part of the Earth is also known as the hydrosphere. Of this amount of water, an estimate of 3% is fresh water and, therefore, drinkable. The rest is undrinkable seawater. Of the 3% fresh drinkable water, it has been estimated that 2% is locked in polar ice. In other words, only 1% of the water on Earth is drinkable.
See also
physical properties of water
chemical properties of water
water purification in treatment plants
Air merupakan sebatian yang terdiri daripada hidrogen dan oksigen. Dianggarkan 70% permukaan Bumi ditutupi air. Bahagian Bumi ini juga dikenali sebagai hidrosfera. Daripada jumlah air ini, dianggarkan 3% adalah air tawar dan, justeru itu, boleh diminum. Yang selebihnya (97%) adalah air laut yang masin. Daripada 3% yang boleh diminum, 2% merupakan ais pada kutub. Dalam perkataan lain, hanya 1% daripada air pada permukaan Bumi boleh diminum.
Baca mengenai
sifat fizikal air