The aim of the experiment was to determine the concentration of nitrate ions in raw and potable water. Gravimetric analysis and spectrophotometer analysis was employed in the methodology techniques. General laboratory glassware, hot plate, UV spectrophotometer, potable water, and standard reagents namely; NaOH (25% WV), C7H5NaO3 (0.5% WV), concentrated H2SO4 and NO-3 standard solution used. The sample was analyzed on the UV-visible spectrophotometer. The graph of absorbance of nitrate versus concentration was plotted with software then concentration was calculated. Results from the experiment are 41.14 mg or 41.14 ppm revealing that the concentration of nitrates in raw and potable water is above the normal standard as prescribed by local standard authority (MBs) which is 10 ppm. Portable water is not recommended for consumption by infants and pregnant women according to the results since it has statistical significance.
Introduction
Water is essential for human development and other living things in the world. Mineral salts such as nitrates dissolve in water and they are colorless in water these salt when reacting with sodium salicylate or salicylic acid form the sodium salt of nitro complex compound. Nitrate ions occur naturally from the nitrogen cycle where nitrogen combines with oxygen. Sometimes nitrates can be reduced to form nitrite ion that contains an unstable oxidation state. Nitrite can also be formed chemically during supply from water tanks plant to the consumer through nitrosomonas bacteria on galvanizing pipes or if residual chlorine is present or the system is not well controlled by the supplier of the water (ICAIR Life system, inc, 1987). Nitrate occurs naturally in surface and groundwater for exactly 1-2 ppm. The presence of natural nitrate has no effect on human health because of the below amount of standard (Oregon Health Authority, 2010) In humans like infants and pregnant women are often vulnerable to health problems from drinking water that has an excess concentration of nitrates above 10 ppm or 10 mg because in many cases it interferes the ability of the blood to transport oxygen throughout the target organs in the body of these groups and these conditions can cause the blue baby syndrome. According to the united states environment protection states that the recommended concentration of nitrates for infants and pregnant women is 3ppm or 3 mg. Infants consuming excess nitrite and nitrates has also other adverse implications for their health such as gastrointestinal disorders. A high intake of nitrite has another effect on the thyroid because it inhibits the intake of iodine since they have similar anions. (WHO, 2010). The presence of excess nitrates or nitrite ions in portable water shows the pollution of the water that is not supposed to consume before treatment.raw water can be used in agricultural industries for irrigation purposes.raw water is the primary source of nitrogen for plants and animals. In most cases excess concentrations of nitrites and nitrates are influenced by human activities such as sewage, disposal of untreated effluents from factories, and use of commercial fertilizers that contain nitrogen like N: P: K. To get lead from this people can reduce nitrate intake by use of distillation process, infants and pregnant should be allowed to consume water that has excess nitrates salts. Sometimes raw water can be used only for bathing, washing clothes, and cleaning dishes (Daniels & Mesner, 2010). The aim of the experiment is to determine the concentration of nitrates ions in the raw and potable water
Materials
A hot plate, UVvisible spectrophotometer, 50 ml measuring cylinder, stoppers, 100 ml Pyrex beakers, pipette filler, 25 ml pipette, micro burette, and reagents were used.
Procedures
The standard solution of nitrate solution was prepared from a standard stock solution of nitrate(500 Î¼gNO-3) by using serial dilution with 10 ml of the solution onto a 100 ml volumetric flask and water was added up to 100 ml mark. The solution was diluted again to produce standard solution B of nitrate solution that has a lower concentration than before, exactly 2.5 g of sodium hydroxide pellets were measured and dissolved with 70 ml of distilled water when cooled the solution was diluted to 100 ml with distilled water in the volumetric flask. Exactly 0.00 ml, 1.00 ml,2.00 ml, 5.00 ml, and 10.00 ml of standard nitrate solution were measured onto 100 ml Pyrex beakers accordingly and exactly of 2. o ml of sodium salicylate solution (0.5% wv ) were added by the pipette. The five Pyrex beakers that contained with the solution were shaken and evaporated on the hot plate. After evaporation, exactly an amount of 1.00 ml volume of concentrated sulphuric acid was added by using a pipette. The beakers were allowed to stand for 10 minutes. Exactly 50.00 ml of distilled water was added to all beakers. Sodium hydroxide (25% wv) mount of 10.00 ml was measured by measuring cylinder onto the five beakers and was mixed thoroughly and allowed to cool down. The solution from five beakers was quantitatively transferred to a 100 ml volumetric flask and diluted with distilled water then the flask was covered by the stoppers and marked according to the volume of nitrates that was added before. The solution was put on the spectrophotometer and the absorbance was measured at a wavelength of 410 nm and the reading was recorded. Excel was used to plot graphs.
Discussions
Nitrate compound occurs naturally from nitrogen element. Nitrogen dissolves in water in form of nitrates or nitrite and it has neither taste nor smell in the water. Nitrates have some benefits to human health when consumed in portable drinking water. The presence of excess nitrates in water beyond the required amounts as instructed by the local standard organization has short or long-term adverse impacts on human health (MBs, 2011). The recommended concentration of nitrates in water for human consumption is about 10.0 mg and above that, it has an adverse effect on pregnant women and young ones, above 40.0 gl has some effects on adults (faculty of materials science and technology in Trnava, 2012).
Conclusion
According to the experimental results, the experiment was successful and it has been found that the concentration of nitrates ions in portable water and raw water is above the recommended standard of nitrate intake for women that have pregnancies and 3 months baby or younger because it can cause blue baby syndrome and death in some cases. The recommended value should below 10 ppm but the sample that was collected is about 41.14 ppm which is high than required (WHO, 2010). Samples should collect for not more than two sites for proper confirmation of the significant figures in the next laboratory session. The local authority should enforce the water supply companies, industries and other companies that dispose of `wastes into water bodies to follow the quality standards of treatments and disposal of wastes.