BOD
Water bodies both produce and consume oxygen. It gains oxygen from the atmosphere and from plants as a result of photosynthesis. For flowing water it would dissolve more oxygen because of the effect of its churning and continuous movement. Waste water containing organic materials are decomposed by microorganisms that utilize the oxygen within the stream. The Biochemical Oxygen Demand (BOD) is the amount of oxygen consumed in this process. Other sources of oxygen consuming waste include storm water runoff from farm areas or septic systems. In this aspect, oxygen is measured in its dissolved form (DO). If more oxygen is consumed than produced, it would affect the eco-system sustained by the waterway or transfer its oxygen consuming inhabitants to lower profile water bodies.
According to APHA, 1992 in their study “Standard methods for the examination of water and wastewater” DO levels fluctuate throughout the day and are influenced by temperature and altitude. The study also states that cold water has a higher oxygen holding capacity than warmer water. Water at 0C had a DO level of 14.60mg/L compared to water at a temperature 36C at a value 6.82mg/L. Similarly, in March 1997 at The University of Rhode Island in the Department of Natural Resources highlighted that salinity, altitude, groundwater inflow and water temperature are some of the factors that influence dissolved oxygen in a water body. The higher the salinity in water reduces the amount of oxygen dissolved. Warm water normally holds less oxygen in solution than cold water. Thermal stratification (heating across different layers) causes depletion of DO and eventually completely depletes levels because there is no replenishment. According to an article by Simpson (1991), ...
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... dichromate, under acidic conditions. A known excess amount of this oxidant is added to the sample and once the process is completed, the COD concentration value is calculated by measuring the remaining amount of oxidant in the solution. This process is usually done through titration by use of an indicator solution. It is measured in milligrams per liter, and indicates the mass of oxygen consumed per liter of solution.
While the Biochemical Oxygen Demand (BOD) test requires 5 days, the COD test only takes about 2-3 hours for full completion and analysis. Within this test it measures all the organic contaminants present in the wastewater sample, including those that are not biodegradable. For the BOD test, toxic compounds such as heavy metals cannot be analyzed therefore, the COD test can be used to measure the strength of wastes that are too toxic for the BOD test.
The purpose of the lab is to figure the concentration of the unknown solution by using the equation of the coordination curve formed by the absorbance of the solution of known
...d the amount of waste in the waterways and the trapping of runoff and litter.
... samples before the incubation of 108 seconds. Then the 100 µL of colour reagent was put to the sample, merged and incubated for further 10 minutes. The absorbance at 615nm and 700nm wavelengths was calculated on the samples in the Cobas analyser and the sample concentration was measure according to :
oxygen out of the blood and uses it in the body's cells. The cells use
Oxygen content: The oxygen within water is derived primarily from submerged plants present within the water. As these plants photosynthesize, Oxygen is released as a byproduct and dissolves into the surrounding water. This increased oxygen content would attract freshwater shrimp to an area, as they are reliant on the surrounding water for the oxygen that is necessary for them to respire aerobically.
About 80% of the State’s surveyed freshwater rivers and streams have good water quality that fully supports aquatic life uses, 17% have fair water quality that partially supports aquatic life uses, and 3% have poor water quality that does not support aquatic life uses. Ten percent of the surveyed rivers do not fully support swimming. The major sources of impairment are agriculture (responsible for 53% of the impaired river miles), urban runoff (responsible for 16%), and construction (responsible for 13%). These sources generate siltation, bacteria, and organic wastes that deplete disssolved opxygen.
Put 1mL of 0.1M cobalt (II) chloride hexahydrate dissolved in 95% ethanol into a test tube. Then add 1mL of deionized water. Tap the end of the test tube to mix the solution and record the pertinent data in section 2 of the Data Table. Discard the solution in the appropriate container as directed to you by your lab instructor.
The purpose of this lab was to calculate the percent composition by mass of oxygen in potassium chlorate.
We were assigned a group and instructed to measure the amount of different ions in that particular fertilizer sample by counting to preform tests. We used the formula SO4 + Agent —> Percipitat + others. Our job was to add 0.25 g of a fertilizer sample to 100 mL of water to dissolve, then add the agent Pb(NO2)3 to the water also, then filter and dry the water, and distinguish the mass. The was accomplished by using the % formula Mass SO4 = Mass Pb(NO3)2 x MW Pb(NO3)2/ MWPb(NO3)2 to gain the percentage, the the formula Mass SO4/MW SO4 =
because most of the world's oxygen is found in water, oxides of metals, and as
The main source of freshwater pollution from the palm oil industry comes from processing wastes. For every metric tonne of palm oil produced, 2.5 metric tonnes of effluent are generated from processing the palm oil in mills. Being the average biochemical oxygen demand (BOD) of palm oil processing effluent 25,000 parts per million, it makes it illegal to discharged it. This is the case in some countries like in Malaysia where the BOD level must be below 100 parts per million before effluent can be legally discharged into streams.
Oxygen (O) is one of the most important ions present in the body, making up 61% of the body’s mass. It aids in the destruction of harmful bacteria, while preserving the bacteria that is beneficial for the body. Oxygen takes on its role, and transfers the bacteria absorbed into the lungs, to the cells, allowing for cell respiration. Oxygen allows for the replacement of old cells, protection of the new ones, production of energy from the food, and decomposition of other foods (“Oxygen and Human Body,” n.d.). Oxygen is also vital to produce an activity known as metabolism, which is ‘the sum of the physical and chemical processes in an organism by which its material substance is ...
Titration is a technological process in which a solution, known as a titrant, is slowly and carefully added from a burrette into a fixed volume of another solution (known as the sample). In an acid-base titration an acid neutralizes a base or vice versa. This process is maintained untill the reaction between the titrant and the sample (acid and the base) is judged to be complete. The reaction is judged to be complete when the endpoint is reached. An endpoint in a titration analysis is referred to as the point at which no more titrant is added due to an observable colour change of an indicator. Indicators can be used to find an endpoint because they change colour when the pH of a solution changes and an endpoint in a titration is an empirical approximation of the equivalence point, which is the point of major pH change in the titration sample due to the fact that equal chemical amounts of reactants have been combined at that point. All indicators have a pH range, which is the range of pH values at which the colour of the indicator changes. Thus
Water pollution is also a major thing in the world because almost 60% of it is fishes. It occurs due to several factors; the industrial waste dumped into the rivers and other water body’s cause am imbalance in the water leading to its severe contamination and deaths. And the infamous Global warming is the emission of greenhouse gases particularly CO2 is leading to global warming.
Fresh water is a limited resource in many parts of the world. And this will become more dearth due to increasing in population, urbanization and climate change. The major fact for this paucity of fresh water is not only due to demand for water but also due to pollution in freshwater ecosystem. Due to the pollution created by human beings in this ecosystem, the usable water has decreased drastically and the cost of purifying the water has increased dramatically. The main sources of water pollution are point source and non point source. Point sources include pipeline discharge of pollutants such as domestic sewage discharge industrial waste effluents from factories or plants, to receiving waters. In contrast, non-point pollution results from storm runoff, which transports polluting materials diffusely over land.