LR EX5 - LAB REPORT PDF

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1 AbstractExperiment of water basic properties 2 is conducted in order to determine the level of chlorine (total and free), iron, sulphates and phosphorus in water samples and ascertain whether the lake water sample comply with Malaysian Water Standards. The sources of water sample including wells, ...

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1.0 Abstract Experiment of water basic properties 2 is conducted in order to determine the level of chlorine (total and free), iron, sulphates and phosphorus in water samples and ascertain whether the lake water sample comply with Malaysian Water Standards. The sources of water sample including wells, lakes, rivers and anywhere contain several level of contamination including heavy metals. The DPD Total Chlorine Powder Pillow, FerroVer Irron Reagent Powder Pillow, PhosVer 3 Phosphate Powder Pillow, SulfaVer 4 Reagent Powder Pillow and DPD Free Chlorine Powder Pillow were used as a reagents. Five sample of 10mL lake sample with different reagent are prepared in sample cell bottles to determine the concentration of chlorine total, chlorine free, sulphate, phosphorus and iron using hach spectrophotometer. The concentration of chlorine total, chlorine free, sulphate, phosphorus and iron are 0.04 mg/L, 0.01 mg/L, 4.0 mg/L, 0.02 mg/L and 0.41 mg/L respectively. The lake water is not suitable for drinking process because of it does not comply with Malaysian water quality standard. The treatment of lake water is needed to be used for daily life activities. The objective is smoothly obtained related to the successfully experiment.

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2.0 Introduction Rapidly moving water, such as in a mountain stream or large river, tends to contain a lot of dissolved oxygen but stagnant water contains less dissolved oxygen. Bacteria in water can consume or used oxygen as organic matter decays. Thus, Eutrophic conditions, which is an oxygen-deficient situation that can cause a water body to "die." due to excess organic material in lakes and rivers Aquatic life can have a challenging time in stagnant water that has a lot of rotting, organic material in it, especially in summer (the concentration of dissolved oxygen is inversely associated to water temperature), when dissolved-oxygen levels are at a seasonal low. Water near the surface of the lake – the epilimnion– is too warm for them, while water near the bottom– the hypolimnion– has too little oxygen. Conditions may become especially serious during a period of hot, calm weather, resulting in the loss of many fish. Demand (BOD) is a measure Biochemical Oxygen Demand or Biological Oxygen. Demand is a measurement of the amount of dissolved oxygen (DO) that is used by aerobic microorganisms when decomposing organic matter in water. If there is a large quantity of organic waste in the water supply, there will also be a lot of bacteria present working to decompose this waste. The demand for oxygen will be high due to all the bacteria so the BOD level also will be high. As the waste is consumed or dispersed through the water, BOD levels will begin to decline. The reality of today’s water quality, where most of it is contaminated by heavy metals, such as phosphorus, iron, sulphate, lead, mercury, cadmium and chlorine.This heavy metals can be one of the main threats to human’s health that have been studied extensively and their risks on human health regularly reviewed by international parties such as the World Health Organization (WHO). The bigger operating industries can also cause the production of heavy metals pollution but nowadays roadways and automobiles are now considered as large possible sources for such hazardous heavy metals. Mostly heavy metals can be harmful and dangerous to human’s health. It can affect the central nervous function leading to mental disorder, damage the blood constituents and may damage the lungs, liver, kidneys and other vital organs promoting several disease conditions. In the human body, these heavy metals are transported and compartmentalized into body cells and tissues binding to proteins, nucleic acids destroying these macromolecules and disrupting their cellular functions. Also, long term accumulation of heavy metals in the body may result in slowing the progression of physical, muscular and neurological degenerative processes that mimic certain diseases such as Parkinson’s disease and Alzheimer’s disease. Repeated long-term contact with some heavy metals or their compounds may even damage nucleic acids, cause mutation, mimic hormones thereby disrupting the endocrine and reproductive system and eventually lead to cancer. Certain heavy metals pollutants also come from fertilizers and sewage, the biggest source of heavy metal pollution definitely is industrialization.

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3.0 Objectives 1. To determine the levels of chlorine (total and free), iron, sulphates and phosphorus in the lake water sample. 2. To ascertain whether the lake water sample comply with Malaysian Water Standards.

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4.0 Theory Many countries that operates numerous heavy industrial factories and have records of polluted environment, which explains lots of news and reports stating the most tap and well water in that country is not safe for drinking purpose. It is even believed that almost all our sources of water, including municipal water systems, wells, lakes, rivers, and even glaciers, contain some level of contamination. The heavy metals penetrate and pollute our natural water sources along with toxic bacteria and other chemical, making people sick as well as causing long term health consequences such as liver damage, cancer and other serious health problems. Even some brands of bottled water have been found to be polluted and harmful in addition to plastic chemical leaching from the bottle. Polluted drinking water can be found anywhere. Even in cities or countries that claim to have healthy water supplies, that are still cases regarding polluted water because the local water may contain unique bacteria. Unsafe drinking water source can spread serious disease, such as potential water-borne illnesses like Hepatitis A, Typhoid Fever and other serious diseases. Most of these diseases have different types of systems, but they all result in abdominal pain, cramping and diarrhea. Usually chlorine is added to water to deactivate and destroy disease-causing microorganisms and is the most widely used as disinfectant. It can react with naturally occurring organic compounds found in water supply, which in turns produce hazardous compounds, known as disinfection by-products (DBPs). Trihalomethanes (THMs) and haloacetic acids are common DBPs. It is undeniably potentially carcinogenic especially to organs such as kidney and liver. Due to this, federal regulations in the United States of America require regular monitoring of the concentration of these compounds in the distribution systems of municipal water systems. Nevertheless, the WHO states that the risks to health from DBPs are extremely small in comparison with inadequate disinfection. In addition, phosphorus occurs naturally in rocks and other mineral deposits. Technically, the rocks release the phosphorus as phosphate ions which are soluble in water and mineralize phosphate compounds breakdown. Phosphate (PO43-) are formed from this element. Phosphate occurs in living and decaying plants and animals as free ions or weakly chemically bounded in aqueous, to sediments and soil, or as mineralized compounds in soils, rocks and sediments. The phosphorus is often scarce in the welloxygenated waters and low levels of phosphorus results in the limitation of production of freshwater systems. Phosphate are generally not toxic to humans or animals unless they are present in high levels of concentration. Phosphorus pollution accelerates a process called eutrophication, which is essentially the process of lake’s biological death due to depleted bioavailable oxygen. The build up of phosphate in the lake water or any surface water ecosystem leads to overproduction of lake or water body which results in the imbalance in the nutrient and material cycling process. There will be massive production of phytoplankton and therefore cause variety of problems ranging from anoxic waters to toxic algal blooms as well as decrease in diversity, food supply and destroying the habitats. Excessive growth of algal due to phosphorus pollution increase water treatments costs, degrades fishing and boating activities as well as impact tourism and property values. 4

Besides, sulfate is also present in almost all-natural water. Sulfate is indeed one of the major dissolved constituents in rainwater. High concentration of sulfate in drinking water cause a laxative effect when combined with magnesium and calcium. Bacteria which is fact attacks and reduce sulfate, cause the formation of hydrogen sulfide gas (H2S). other than that, there are also the present of iron in the natural waters. The maximum contaminant level (MCLs) of iron is 0/3 mg/L. iron ingestion is not generally unhealthy and necessary in small amounts. However, research has found that exposure to high levels of iron can lead to heart disease, cancer and diabetes. Iron is often included in supplements and enriched products. It also contains in red meat, therefore easily to be consumed. Thus, in this experiment, absorption spectroscopy will be used to detect the level concentration of chlorine, sulfate, iron and phosphorus in the lake water sample. The basic premise of spectroscopy is that the amount of electromagnetic radiation emitted comes from the amount of energy released during transition of an analyte from the ground state to the excited state or vice-versa. Theoretically, colored aqueous solutions have chemical species contents which absorb significant wavelengths of light. Similarly, heavy metals can be identified via absorption of wavelengths of light. Absorption spectroscopy operates on the measuring principle of light before and after it passes through an aqueous metal solution. The amount of light absorbed by the chemical species in the sample is equivalent to the difference in the amount of light before it enters the sample and after it exits the sample. For the purpose of light to be absorbed by chemical species, the light must be set to a specific wavelength. Every chemical species absorbs distinct wavelength of light. In absorption spectroscopy, the wavelength of light absorbed by a metal in solution are detected.

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5.0 Materials and Apparatus 5.1 Apparatus Apparatus 1 10 mL round sample cell bottles 2 Measuring cylinder 3 Tissue wiper

4 Spectrophotometer 5 Soap 6 Brush

Description To keep water sample and transport it to the spectrophotometer without contamination. To measure the volume of lake water. To eliminate the impressions such as fingerprint of round sample cell bottle before measure in spectrophotometer. To measure the concentration of chemical in lake water. To eliminate or clean the sample cells. To eliminate or clean the sample cells.

5.2 Materials 1. Lake Water Sample 2. DPD Total Chlorine Powder Pillow 3. FerroVer Iron Reagent Powder Pillow 4. 5. 6. 7. 8.

PhosVer 3 Phosphate Powder Pillow SulfaVer 4 Reagent Powder Pillow Distilled water Acid Persulfate DPD Free Chlorine Powder Pillow

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6.0 Procedure

Experiment A: Chlorine Total (0.02 to 2.00 mg/L) – Using DPD Method 1. The hach programs was entered and the program 80 Chlor. F&T. was selected and started the program. 2. The 10 mL of lake water sample was filled in a round sample cell. 3. The content of one DPD Chlorine Total Powder Pillow was added to the sample cell. The sample cell was swirled for 20 seconds to mix the sample. 4. From the program, the timer icon was selected and three-minute reaction period will begin. The step 5 and 6 were performed during this time period. 5. Another round sample cell was filled with 10mL of distilled water. The sample cell wiped with suitable wiper and placed it into the cell holder. 6. The zeroing program was selected and the 0.00 mg/L Cl2 was displayed. 7. The prepared sample wiped and then placed it into the cell holder within few minutes after the timer beep. 8. The read program was selected and the result was recorded.

Experiment B: Chlorine Free (0.02 to 2.00 mg/L) – Using DPD Method 1. The hach programs was entered and the program 80 Chlor. F&T. was selected and started the program. 2. The 10 mL of lake water sample was filled in a round sample cell. 3. 4. 5. 6.

The sample cell wiped with suitable wiper and laced it into the cell holder. The zeroing program was selected and the 0.00 mg/L Cl2 was displayed. The second round sample cel was filled with 10mL of lake water sample. The content of one DPD Chlorine Total Powder Pillow was added to the second sample cell. The sample cell was swirled for 20 seconds to mix the sample and immediately proceed to step 7. 7. The prepared sample wiped and then placed it into the cell holder within one minutes of adding the reagent. 8. The read program was selected and the result was recorded.

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Experiment C: Iron Total (0.02 to 3.00 mg/L) – Using FerroVer Method. 1. The hach programs was entered and the program 256 iron, FerroVer. was selected and started the program. 2. The 10 mL of lake water sample was filled in a round sample cell. 3. The content of one FerroVer Iron Reagent Powder Pillow was added to the sample. The sample cell was swirled to mix the prepared sample. 4. From the program, the timer icon was selected and three-minute reaction period will begin. Sample that contains rust should react for at least 5 minutes. 5. Another round sample cell was filled with 10mL of distilled water. 6. The prepared sample wiped with suitable wiper and then placed it into the cell holder when the timer beeps. 7. The zeroing program was selected and the 0.00 mg/L Fe was displayed. 8. The prepared sample wiped and then placed it into the cell holder. 9. The read program was selected and the result was recorded.

Experiment D: Phosphorus Reactive – Orthophosphate (0.02 to 2.50 mg/L) – Using PhosVer3 (Ascorbic Acid) Method. 1. The hach programs was entered and the program 490 P React. PV. was selected and started the program. 2. The 10 mL of lake water sample was filled in a round sample cell. 3. The content of one FerroVer Iron Reagent Powder Pillow was added to the sample. The sample cell was swirled to mix the prepared sample immediately. 4. From the program, the timer icon was selected and two-minute reaction period will begin. 5. Another round sample cell was filled with 10mL of distilled water. 6. The prepared sample wiped with suitable wiper and then placed it into the cell holder when the timer beeps. 7. The zeroing program was selected and the 0.00 mg/L PO43- was displayed. 8. The prepared sample wiped and then placed it into the cell holder. 9. The read program was selected and the result was recorded.

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Experiment E: Sulfate (2 to 70 mg/L) – Using SulfaVer4 Method. 1. The hach programs was entered and the program 680 Sulfate was selected and started the program. 2. The 10 mL of lake water sample was filled in a round sample cell. 3. The content of one SulfaVer 4 Reagent Powder Pillow was added to the sample. The sample cell was swirled to mix the prepared sample. 4. From the program, the timer icon was selected and five-minute reaction period will begin. 5. Another round sample cell was filled with 10mL of distilled water. 6. The sample cell wiped with suitable wiper and then placed it into the cell holder when the timer beeps. 7. The zeroing program was selected and the 0.00 mg/L SO42- was displayed. 8. The prepared sample placed into the cell holder within five minutes after the timer beeps. 9. The read program was selected and the result was recorded. 10. The sample cells cleaned with soap and a brush.

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7.0 Results Table 1 – The Level Of The Substances in The Lake Water Sample Substances

Chlorine Total

Chlorine Free

Sulfate

Phosphorus

Iron

Reagent

Colour of Solution Colourless

Concentration of substances (mg/L) 0.02

Mass os Substances (mg) 4 × 10-4

DPD Total Chlorine powder pillow DPD Free Chlorine powder pillow Sulfate ver 4 reagent powder pillow Phosphorus ver 3 Phosphate powder pillow Ferro ver Iron Reagent powder pillow

Colourless

0.01

1 × 10-4

Yellowish / cloudy

4.0

0.04

Colourless

0.02

2 × 10-4

Light pink

0.41

4.1 × 10-3

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8.0

SAMPLE OF CALCULATIONS

Sample Calculation For Mass Of The Substances :-

Sample 1 : Chlorine Total (Cl2) Concentration of substance : 0.04 mg/L Volume of a Sample : 10mL/1000 = 0.01 L

= 4 × 10−4𝑚𝑔 Sample 2 : Chlorine Free (Cl2) Concentration of substance : 0.01 mg/L Volume of a Sample : 10mL/1000 = 0.01 L

= 1 × 10−4𝑚𝑔

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Sample 3 : Sulfate (SO42-) Concentration of substance : 4 mg/L Volume of a Sample : 10mL/1000 = 0.01 L

= 4 × 10−2𝑚𝑔 Sample 4 : Phosphorus, Reactive Concentration of substance : 0.02 mg/L Volume of a Sample : 10mL/1000 = 0.01 L

= 2 × 10−4𝑚𝑔

Sample 5 : Iron Total (Fe) Concentration of substance : 0.41 mg/L Volume of a Sample : 10mL/1000 = 0.01 L

= 4.1 × 10−3𝑚𝑔 12

9.0 DISCUSSION The objectives of the experiment is to determine the levels of chlorine consists of total and free, iron, sulfates and phosphorus in the lake water sample and ascertain whether it compliment the Malaysia Water Standards. The sample is taken from Tasik Seksyen 7 Shah Alam. The reagents used are, DPD Free Chlorine Powder Pillow, DPD Total Chlorine Powder Pillow, Sulfa Ver 4 Sulfate Reagent Powder Pillow, Phos Ver 3 Phosphate Powder Pillow, Ferro Ver iron Reagent Powder Pillow and Chroma Ver 3 Reagent Powder Pillow.

Determination levels of chlorine were made based on amount of total and free Chlorine. The total chlorine is the sum of the Combined and Free Chlorine present in the water and combined Chlorine is the chlorine that have been used up to sanitize the water. The existance of chlorine in water were helpful in disinfect or killing possibly harmful microorganisms. The experiment used DPD method asthe method is the most accurate way to measure rigid amount for free chlorine and total chlorine. (Chlorine Residual Testing (CDC))

The lake water sample remained colourless after the addition of the reagent. The result obtained for free chlorine is 0.01mg/L and total chlorine is 0.02mg/L. Based on the free and total chlorine value, the lake water sample do not comply with Ministry of Health Malaysia which propose 0.2mg/L – 5.0mg/L (Free Chlorine) and not less than 1.0mg/L for combined chlorine in the Drinking Water Quality Standard.To summaries it is recommended to avoiding drinking or in contact with the lake water as the result gain from the experiment being carried show that it is not comply with Ministry of Health Malaysia which propose 0.2mg/L – 5.0mg/L (Free Chlorine) and not less than 1.0mg/L for combined chlorine for drinking and also against Safe Chlorine Level for Swimming Pools since the range is too low which is below 1mg/L. The low chlorine value indicates that the lake water need further chlorine treatment to ensure the harmful microorganism disinfect effectively due to safety issues.

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Based on this experiment, the concentration of sulfate recorded is 4.0mg/L. It shows that the amount of sulfate is acceptable since it is below the recommended limits for water used which is 250 mg/L. But the lake water is still not suitable for drinking purpose since the other heavy metals did not comply the standard. In humans, concentrations of 500 to 750 mg/L can cause a temporary laxative effect. However, the doses of several thousand mg/L did not cause any long-term ill effects. Sulfate ions also are involved in complexion and precipitation reactions which affect solubility of metals and other substances. Sulfate are not considered toxic to plants or animals at normal concentrations. Theoretically, phosphorus is the eleventh-most abundant mineral in the earth's crust and does not exist in a gaseous state. Phosphorus in water exists in either a particulate phase or a dissolved phase...