TABLE OF CONTENTS 1.0 Experiment title
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2.0 Objectives
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3.0 Apparatus
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4.0 Introduction
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5.0 Procedure
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6.0 Data, Observation and Calculation 2 7.0 Discussion
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8.0 Conclusion
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9.0 References
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10.0 Appendix
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1.0 Experiment Title Suspended Solids (SS) 2.0 Objective To determine the suspended solids in a given sample 3.0 Apparatus 1. Two Petri dishes 2. Drying oven 3. Dessicator 4. 2 graduated cylinders 5. Beaker 6. 2 filter papers 7. Analytical balance 8. Conical flask 4.0 Introduction This experiment is done to determine the total suspended solids in a 50 ml of water sample taken from the pond behind the Block B building at UiTMSamarahanKampus 1. This experiment is done 2 times to determine the average value of the suspended solids. Total solids are the material residue left after evaporation of a sample and its subsequent drying in an oven. Some factors that affect the separation of suspended from dissolved solids are pore size, porosity, particle size and amount of material deposited on the filter paper. Dissolved solids are solids that passes a 2 µm while suspended solids is the portion retained on the filter. According to “Total Suspended Solids (TSS)”, high concentration of suspended solids will make the water warmer thus decreasing the ability of water to hold oxygen and this will also prevent aquatic lives to live in the water. 5.0 Procedure Preparations: 1. Two filter papers were marked as A and B respectively. 2. The petri dishes and the filter papers were placed in the oven at 105°C for 1 hour. 3. The filter papers and petri dishes were removed from the oven after 1 hour. 4. The filter papers and petri dishes were then placed in the dessicator for 4 minutes. 5. The weight of all the apparatus were taken immediately after completing step 4. Experiment: 1. Both filter papers were folded into a cone shape and placed on top of the conical flask. 2. 10 ml of distilled water is passed through both of the filter papers 3 times to ensure that the filter paper is clean. 1
3. 50 ml of water sample from the pond is filtered. 4. The filter papers were placed on the petri dishes and dried in the oven at 105°C for 1 hour. 5. The final weight of the filter papers are weighed and recorded.
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6.0 Data, Observation and Calculation Table 6.1: Experiment results Filter Paper
A
B
Sample volume
50
50
(mL) Filter Paper, X
1309
1303
(mg) Filter Paper + dried
1258
1256
Average
-102 0
-940
-980
residue, Y (mg) SS (mg/L)
SS (mg/L) =
( Y −X ) ×1000 mLsample
X = Mass of empty filter (mg) Y = Mass of filter paper + dried residue (mg) Calculation of data: SS (mg/L) =
( 1258−1309 ) × 1000 50 mL
= -1020 mg/L
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7.0 Discussion From the data obtained and calculated, the value of suspended solid for sample 1 is higher than sample 2, which means that sample 1 might contain more organic matter than sample 2. However, the value for the suspended solids for both samples is negative. By referring to the National Water Quality Standards for Malaysia, it is found out that this value is not in range, which means that the experiment is unsuccessful probably due to an error during the experiment by the experimenters. This is probablydue to the filter paper that does not dried for a longer period of time in the oven, therefore the residual moisture might not be totally removed which affect the reading of weight of the filter paper. Another error is that the samples might have been cooled under improper desiccation. Next, the water was disturbed while it is being filtered; where the water was not let to trickle freely, it was somewhat ‘forced’, by moving the filter paper; and this might also contribute to the negative value that is obtained. Therefore, some precautions must be observed while performing the experiment which is students should be aware that prolonged drying may result in loss of constituents, particularly nitrates and chlorides. Besides that, volume of samples should be adjusted to have residue left after drying as 100 to 200mg. It is mainly to prevent large amount of residue in entrapping water during evaporation. Lastly, the experimenter should not forget to dry the filter paper in the oven so the value of total suspended solid can be obtained. The permissible values of suspended solids are: 25 mg/l for water in Class I which is water in conservation of natural environment, where no treatment is necessary and habitat for very sensitive aquatic species 50 mg/l for water in Class IIA which needs conventional treatment and habitat for sensitive aquatic species 50.0 mg/l for water that is used for recreational purpose; with body contact 150 mg/l for water in Class III where extensive treatment is required and is common with economic values and tolerant species and also for livestock drinking 300 mg/l for water in Class IV which is water in irrigation 300 mg/l for water in Class V which is other than waters in Class I,II,III and IV (Source: National Water Quality Standards) 8.0 Conclusion 4
As the conclusion, the samples cannot be classified based on DOE Water Quality Index Classification because the results from the experiment is not valid, therefore it cannot be determined whether the samples is clean, slightly polluted or polluted and the objective for this experiment; which is to determine the suspended solids in a given sample cannot be achieved.
9.0 References 1. Standard Methods for the Examinations of Water and Wastewater, retrieved from ftp://law.resource.org/pub/us/cfr/ibr/002.apha.method.2320.1992.ht ml on 25th July 2015. 2. “Total Suspended Solids (TSS)”, retrieved from https://www.ndhealth.gov/WQ/SW/Z6_WQ_Standards/WQ_TSS.htm on 25th July 2015. 3. National Water Quality Standards, retrieved from http://www.gunungganang.com.my/pdf/Malaysian-PoliciesStandards-Guidelines/Standards/National%20Water%20Quality %20Standards.pdf on 25th July 2015 4. Total and Volatile Suspended Solids. Retrieved fromwww.ce.wsu.edu/facstaff/~yonge/ce515/TSSVSS.pdf on 25th July 2015.
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10.0 Appendix Table 10.1: National Water Quality Standard for Malaysia
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