Water Chemistry Essay

Submitted By matildarose
Words: 1851
Pages: 8

Abstract:
Water can be found almost everywhere on Earth. It is a very unusual material, with lots of peculiar chemical and physical properties. Many substances dissolve in water and therefore untreated water is extremely unsafe for human consumption. It contains multiple harmful contaminants which must be removed during the water treatment process and it must be monitored constantly to ensure that its pH, turbidity and many other areas are within the required levels.
According to the primary and secondary results of this report, the correct level of dissolved oxygen is extremely important in drinking water and the amount of alum, which must be added to untreated water to lower the turbidity, is relatively high. Introduction:
Water is a very unusual and unique compound and is the only natural substance which can be found on Earth as a liquid, solid and gas (The National Science Foundation,, n.d.). One water molecule consists of one oxygen atom and two hydrogen atoms, which are bound together by a covalent bond (Granger, 2014). Water is a polar molecule, meaning that there is an uneven distribution of electron density (Biology Arizona, 2003). The electrostatic attraction between the hydrogen and oxygen atoms allows water to interact with itself and form a highly organised inter-molecular network, through the type of dipole-dipole interaction known as hydrogen bonding (Lower, 2014). This hydrogen bond gives the water unique abilities such as adhesion, cohesion and solubility.
Water is the foundation of life but clean, safe drinking water is limited and strict procedures must be undertaken to ensure that we have a constant supply. Water covers nearly 71% of the Earth’s surface, however, only 3% of this is freshwater and of that only 0.003% is fit for human consumption (Lower, 2014). The rest is unaffordable to extract, highly polluted or inaccessible in glaciers, ice caps or in the atmosphere and soil (Gladstone Area Water Board, 2014). Therefore it is essential that we preserve and manage the earth’s limited supply of suitable, accessible drinking water.
The Gladstone Area Water Board supply’s water in two forms from Lake Awoonga - untreated water which makes up 77% and treated drinking water which makes up the other 23% (Gladstone Area Water Board, 2014). Water supplied by GAWB for human consumption is treated to the National Health and Medical Research Council's Australian Drinking Water Guidelines and experiences extensive testing throughout the treatment plant to ensure that it is delivered safe (Smith S. , 2014). Main Body:
Water that is going to be used for human consumption should be clean, safe and free of any physical matter, harmful chemical substances or pathogenic micro-organisms (Smith, Monteath, & Gould:, 2006). It should be clear, well ventilated and have no unpleasant tastes or odours. The water should be appropriate to use for all primary and secondary contact including drinking, cooking and bathing. The acceptable concentrations of dissolved substances (refer appendix 1) must be strictly monitored to ensure that the water is pleasant for human consumption.
Water is an excellent solvent and as a result when untreated, can contain a variety of harmful substances and components which need to be removed or reduced for the water to be considered safe (Advameg, 2014). Infectious diseases caused by pathogenic bacteria, viruses and protozoans (refer appendix 2) are the biggest health risk associated with drinking water. These must be removed from the water during the treatment process for it to be considered safe (New Jersey Department of Health, 1997). There is also numerous other contaminants (refer appendix 3), which must be chemically derived from raw water to ensure that it meets drinking water standards. The drinking water temperature, pH, colour, dissolved oxygen, hardness and total dissolved solids should also be closely monitored to ensure it is safe for human…