Nitrite and Nitrate Lab Report PDF

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ENVIRONMENTAL ENGINEERING LABORATORYECW 568OPEN-ENDED LAB REPORTTITLE OF EXPERIMENT : NITRITE AND NITRATEDATE OF EXPERIMENT : 11 NOVEMBER 2020GROUP : EC220 /6C4AGROUP MEMBERS 1. INTAN AFIQAH BINTI KABRI (2019528043)2. AIN NAZIRA BINTI MOHD SABANDI (2019582535)3. HAIDHATUL AMIZZA BINTI AZMI (20195281...

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ENVIRONMENTAL ENGINEERING LABORATORY ECW 568 OPEN-ENDED LAB REPORT

TITLE OF EXPERIMENT DATE OF EXPERIMENT GROUP GROUP MEMBERS

: NITRITE AND NITRATE : 11 NOVEMBER 2020 : EC220 /6C4A 1. INTAN AFIQAH BINTI KABRI (2019528043) 2. AIN NAZIRA BINTI MOHD SABANDI (2019582535) 3. HAIDHATUL AMIZZA BINTI AZMI (2019528193) 4. MUHAMMAD ZULHILMI BIN MUHAMMAD ZULHAZLI (2019528147) 5. LLOYDRYEN NAWANG SIMON (2019582329)

LECTURER LEVEL OF OPENESS

: DR. DZULAIHKA BINTI KHAIRUDDIN : 2 MARKS

COMMENTS

INTRODUCTION BASIC CONCEPTS METHODOLOGY

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RESULTS&ANALYSIS

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DISCUSSION

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CONCLUSION

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ORGANIZATION

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TOTAL MARKS

TITLE: NITRITE AND NITRATE

INTRODUCTION Nitrate and nitrite are naturally occurring ions that are part of the nitrogen cycle. Nitrate is used mainly in inorganic fertilizers and sodium nitrite is used as food preservatives, especially in cured meats. The nitrate concentration in groundwater and surface water is normally low but can reach high levels as a result of leaching or runoff from agricultural land or contamination from human or animal wastes because of the oxidation of ammonia and similar sources. Anaerobic conditions may result in the formation and persistence of nitrite. Chloramination may give rise to the formation of nitrite within the distribution system if the formation of chloramine is not sufficiently controlled. The formation of nitrite is because of microbial activity and may be intermittent. Nitrification in distribution systems can increase nitrite levels, usually by 0.2 – 1.5 mg/litre.

OBJECTIVES 1. To measure the concentration of nitrate and nitrite in water sample. 2. To analyse data and interpret the results of the nitrate and nitrite experiment.

LEARNING OUTCOMES At the end of the laboratory activities, students would be able: • To acquire and develop sublime psychomotor skills in conducting laboratory experiments. • To work as a team, demonstrate leadership and enhance communication skills through discussion.

PROBLEM STATEMENT Water samples were collected from two (2) different locations labelled as Bottle A and Bottle B. In order to identify the origin of the water samples collected, you are required to carry out the Nitrate and Nitrite test on the water samples by referring to the correct procedures and using the appropriate apparatus available in the laboratory.

APPARATUS • Mixing cylinder • Stopper • 10 ml square sample cell • Spectrophotometer PROCEDURE a) Nitrate test 1. The spectrophotometer was switched on. 2. The program “351 N Nitrate LR” was clicked on the spectrophotometer. 3. About 25 ml graduated mixing cylinder was filled with 15 ml of water sample A. 4. NitraVer 6 Reagent Powder Pillow was added into the mixing cylinder. 5. The stopper was put at the mixing cylinder. 6. The 3 minutes-timer-button was clicked on the spectrophotometer. 7. The step before was to allow the powder to properly mix with the water sample. 8. Then the mixing cylinder was shaken for 3 minutes. 9. The 2 minutes-timer-button was clicked after 3 minutes-timer ran out. 10. The previous step was to allow the powder to properly mix with the water sample 11. About 10 ml of the water sample was carefully poured into a clean square sample cell when the timer expired. Noted that do not transfer any cadmium particles to the sample cell. 12. As for the prepared sample preparation, NitriVer 3 Nitrite Reagent Powder Pillow was added into the sample cell. 13. The 30 seconds-timer-button was clicked on the spectrophotometer which was to allow the powder to properly mix with the water sample. 14. The sample cell was capped and shaken gently during the 30 seconds-timer. A pink colour was developed if nitrate was present. 15. The 15 minutes-timer-button was clicked on the spectrophotometer. 16. This was to allow the powder to properly mix with the water sample. 17. As for the blank sample preparation, a second square sample cell was filled with 10 ml of original water sample when the timer expired. 18. The blank sample was wiped and inserted into the cell holder with the fill line facing right.

19. The zero button was clicked on the spectrophotometer to ensure the spectrophotometer was properly cleared. 20. The blank sample was taken out and the prepared sample was wiped and inserted into the cell holder with the fill line facing right. 21. The read button was clicked on the spectrophotometer. 22. The concentration of nitrate in the water sample was obtained and recorded. 23. The procedure was repeated for water sample B. 24. The data was recorded.

b) Nitrite test 1. The spectrophotometer was switched on. 2. The program “371 N Nitrite LR PP” was clicked on the spectrophotometer. 3. A square sample cell was filled with 10 ml of water sample A. 4. As for the prepared sample preparation, NitriVer 3 Nitrite Reagent Powder Pillow was added into the water sample. The sample cell was swirled to dissolve the powder pillow. A pink colour was developed if nitrite was present in the water sample. 5. The 20 minutes-timer-button was clicked on the spectrophotometer. 6. This was to allow the powder to properly mix with the water sample. 7. As for the blank sample preparation, a second square sample cell was filled with 10 ml of water sample when the timer expired. 8. The blank sample was wiped and inserted into the cell holder with the fill line facing right. 9. The zero button was clicked on the spectrophotometer to ensure the spectrophotometer was properly cleared. 10. The blank sample was taken out and the prepared sample was wiped and inserted into the cell holder with the fill line facing right. 11. The read button was clicked on the spectrophotometer. 12. The concentration of nitrite in the water sample was obtained and recorded. 13. The procedure was repeated for water sample B. 14. All the result was recorded.

Data Analysis Table 1: Analysis of Nitrate Sampling Location

Nitrate (mg/l) Sample A

Sample B

Average (mg/l)

L1

0.010

0.010

0.010

L2

0.210

0.220

0.215

L3

0.210

0.220

0.215

L4

0.451

0.440

0.446

Table 2: Analysis of Nitrite Sampling Location

Nitrite (mg/l) Average (mg/l)

Sample A

Sample B

L1

0.006

0.004

0.005

L2

0.115

0.120

0.118

L3

0.117

0.120

0.119

L4

0.201

0.197

0.199

Table 3: Comparison between two standards

Average (mg/l)

Types

L1

L2

L3

L4

Nitrate

0.010

0.215

0.215

0.446

Nitrite

0.050

0.118

0.119

0.199

National Water Quality Standard for Malaysia

Acceptable Value for Raw water Quality and Drinking Water Quality

Class IIA 7.0 Class IIA 0.4

10

-

DISCUSSION This experiment was conducted to measure the concentration of nitrate and nitrite in water sample. Water sample taken in Sungai Klang at different four sampling location (L1, L2, L3, L4). Two water sample (SA, SB) were collected at each location and the water sample were taken to laboratory for the concentration measure of nitrate and nitrite. Spectrophotometer is the device in the laboratory to measure the concentration of nitrate and nitrite. The average reading of two sample at each sampling location were recorded. In nitrate, the nitrogen is bonded with three oxygen atoms, while in nitrite the nitrogen is bonded with two oxygen atoms. Nitrate (NO3-) can found naturally in the environment. Nitrite (NO2-) are less present in most water supply except in reducing environment because Nitrate is the more stable in oxidation state (WHO,2017). Nitrates are widely use as fertiliser in agriculture. Nitrate and nitrite are widespread contaminants of vegetables, fruits, and waters (Aires,2013). Excessive level of nitrates in the water especially in the river or lake can threatened the aquatic life. When nitrates enter the water, algae have nitrates as their food resources and algae will become excessively growth and then called as eutrophication. After that, algae will used up the oxygen content in the water and will cause depletion of oxygen level that will end up the other living in the water such as fish did not have enough oxygen end up die. The excessive intake of nitrates and nitrate can give health effect. In some circumstances, however, drinking-water can make a significant contribution to nitrate and, occasionally, nitrite intake. In the case of bottle-fed infants, drinking-water can be the major external source of exposure to nitrate and nitrite (WHO,2017). Infants younger than 4 months of age are the highest risk group for harm from exposure to nitrates. Based on the data given at Table 1 and Table 2, we can see that at location 1, the average value of Nitrate are 0.010mg/l while the average value of Nitrite at are 0.005mg/l. These show that the Nitrate concentration at location 1 are considered as low because it is still on the range of 0 to 18 mg/l which is normally low concentration of Nitrate meanwhile for Nitrite it can be used for drinking water because the Nitrite levels are below 0.1 mg/l. This two value are very low because the water are at upstream. The value of Nitrate and Nitrite concentration can be increase due to of agricultural runoff, refuse dump or contamination with human or animal wastes. We can see that the concentration keeps increasing from the upstream to the downstream. At location 2 and 3, the value of Nitrate and Nitrite are increasing. This because the water has been contaminated by the wastewater treatment. For the Nitrate, the average

concentration at both sample are 0.215mg/l while for Nitrite, the average concentration are 0.118 mg/l and 0.119 mg/l. For the last sample, at location 3 was located at the downstream which the value of both concentration are the highest during this experiment conducted. The average value of concentration for Nitrate are 0.446 mg/l while for the value of concentration of Nitrite are 0.199 mg/l. These two value are increase because there is an agricultural plot near the downstream where the Nitrate and Nitrite can been derive from the fertilizer that are used by the farmer which is the nitrogen fertilizer. In the soil, the bacteria will convert the various forms of nitrogen into Nitrate. Nitrates and Nitrites are natural constituents of plant material, and they are normally present in high levels, particularly in green vegetables (Correia et al. 2010). Although, considering the fact that Nitrate is an essential component of plant content, it has the ability to accumulate in tissues and thus Nitrate from fertilizers could accumulate in large-scale vegetables. That is why farmer always use the nitrogen fertilizer at their plant. As a result, it effected the water at the river due to the agricultural activities and make the concentration of Nitrate and Nitrite increase. Furthermore the data at table 3 shown the comparisons of Nitrate and Nitrite that collected from the spectrophotometer. The standard that we used for comparison of both concentration are the National Water Quality Standard for Malaysia and Acceptable Value for Raw Water Quality and Drinking Water Quality. From the data interpretation, we can observe that all the samples are for each location (L1, L2, L3 and L4) are categorized as Nitrate and Nitrite in Class IIA by referring to National Water Quality expectations for Malaysia at Table 4. In this class. The standard treatment for the water supply of this river is required. However, the river is considered safe for the public and the aquatic life as long as is not vulnerable to pollution because there is sensitive aquatic animals exist there. It is important to refer from the standard in order to monitor the quality of water in the river for more protective approach. Based on the Table 6, the suitable value for nitrate (NO₃) and Nitrite (NO₂) values are 7.0 mg/l and 0.4 mg/l respectively. So, as we can see in Table 3, the acceptable value of both concentrations was not exceeded.

Conclusion Based on the water samples collected from the two different locations labelled as Bottle A and Bottle B, we were able to determine the nitrite and nitrate concentration in the water sample. At location 1, the average value of Nitrite are 0.005mg/l, and for Nitrate, the average value are 0.010mg/l. From this value, we can see that Nitrate concentration at location 1 are considered as low since it is in the range of 0 to 18 mg/l. With the Nitrate value below 0.1 mg/l, it means that it can be used for drinking water. At location 2 and 3, the Nitrate’s average concentration for both samples are 0.215mg/l while for Nitrite, the average concentration for location 2 and 3 are 0.118 mg/l and 0.119 mg/l respectively. For the last location, the average value of concentration for Nitrate are 0.446 mg/l, and for Nitrite, the average concentration are 0.199 mg/l. When comparing the concentrations to the National Water Quality Standard for Malaysia, all the samples for each location (L1, L2, L3 and L4) are categorized as Nitrate and Nitrite in Class IIA. Which means, the uses are for water supply II where conventional treatment are required, and Fishery II where it have sensitive aquatic species. From the result obtained, we know that nitrate concentration in groundwater and surface water is normally low but it can reach high levels as a result of leaching or runoff from agricultural land or contamination from human or animal wastes because of the oxidation of ammonia and similar sources. When comparing to the Drinking Water Quality Standard, the value of nitrate and nitrite are acceptable as it does not exceed the standard.

REFERENCES 1. WHO. (2017). Nitrate and nitrite in drinking-water World Health Organization. Retrieved

from

https://www.who.int/water_sanitation_health/dwq/chemicals/nitratenitrite2ndadd.pdf. 2. Correia, M., Barroso, Â. Barroso, M. F., Soares, D., Oliveira, M. B. P. P., & DelerueMatos, C. (2010). Contribution of different vegetable types to exogenous nitrate and nitrite

exposure.

Food

Chemistry,

120(4),

960-966.

Retrieved

https://www.sciencedirect.com/science/article/pii/S0308814609013405

from

3. Aires, A., Carvalho, R., Rosa, E. A., & Saavedra, M. J. (2013). Effects of agriculture production systems on nitrate and nitrite accumulation on baby‐leaf salads. Food science

&

nutrition,

1(1),

3-7.

Retrieved

from

https://onlinelibrary.wiley.com/doi/full/10.1002/fsn3.1. 4. Masime Jeremiah, O., Ruth, W., Jane, M., & Charles, O. A Comparison of the Levels of Nitrate, Nitrite and Phosphate in Homemade brews, Spirits, in Water and Raw Materials in Nairobi County Using UV-Visible spectroscopy. Retrieved from https://www.researchgate.net/profile/Jeremiah_Masime/publication/259313366_A_C omparison_of_the_Levels_of_Nitrate_Nitrite_and_Phosphate_in_Homemade_brews_ Spirits_in_Water_and_Raw_Materials_in_Nairobi_County_Using_UVVisible_spectroscopy/links/00b7d52afcc1cede0a000000.pdf. 5. Engineering Services Division, Ministry of Health Malaysia, Drinking Water Quality Standard, retrieved from: https://environment.com.my/wpcontent/uploads/2016/05/Drinking-Water-MOH.pdf 6. Malaysia Water Quality Standard. Retrieved from https://www.doe.gov.my/portalv1/wp-content/uploads/2019/05/Standard-Kualiti-AirKebangsaan.pdf

Appendix

Table 4: National Water Quality Standard for Malaysia

Table 5: Water Classes and Uses

Table 6: Drinking Water Quality Standard...