Experiment 3: Determination of Lead in Anchovies by Cold Vapour GenerationAtomic Absorption Spectrometry Objectives: 1 To determine Pb2+ content in anchovies through wet digestion method. 2 To use standard addition method in calibration procedure. Introduction: Atomic absorption spectrometry (AAS) is an analytical technique that measures the concentration on elements. It’s very sensitive because it can measure down to parts per billion of a gram (ɥgdm -3) in a sample. Atomic absorption occurs when atom at ground state absorb energy in the form of light of a specific wavelength and is elevated to an excited state. The amount of energy absorb will increase as the number of atoms selected element in the light path increases. The concentration unknown sample can be determined by measuring the amount of light they absorb. The objective of this experiment is to determine the Lead (Pb 2+) content in anchovies. This instrument was used in determining the Pb 2+ content in anchovies. Lead is naturally occurring element found in small amounts in earth’s crust. While it has some beneficial uses, it can be toxic to human and animals causing of health effects. It can damage the nervous system and causes brain disorders. Fish can accumulate substantial concentrations of heavy metal in their tissues due to water that has been contaminated by chemicals. Instrumentation: 1 Instrument model : Perkin Elmer-FIMS 400 2 Serial No: A 40158010802 3 Location: 305 Apparatus: Beaker250ml, volumetric flask 250ml, filter paper, filter funnel, pipette, hot plate Chemicals: 100ppm Pb2+ standard solution, HNO3, H2O2, Procedures: Sample preparation: The anchovies was cut in small pieces and dried in oven at 110 ℃ for 24 hours. Three portion of the sample was weigh ranging from 0.5 to 1.0 g and transfer into a beaker. 7ml of concentrated HNO3 and 1ml of H2O2 was added into each beaker. The beaker was put onto a hot plate for 20 minutes. After that, the solution was filtered using a filter funnel equipped with filter paper and combining. The sample was run for three times to obtained the calibration points. The calibration curve was plot and the concentration of Pb2+ in the sample was determined. Standard preparation: 1 Preparation of 100ppm Pb2+ standard solution M1V1 = M2V2 (1000mg/L)(x) = (100mg/L)(0.25L) X = 0.025 L 2+ 25ml of 1000ppm of Pb stock solution was pipette into 250ml of volumetric flask. The solution diluted by using deionized water. 2 Preparation of Pb2+ standard solution a 2ppm standard solution M1V1 = M2V2 (100mg/L)(x) = (2mg/L)(0.25L) X = 0.005 L b 4ppm standard solution M1V1 = M2V2 (100mg/L)(x) = (4mg/L)(0.25L) X = 0.01 L c 6ppm standard solution M1V1 = M2V2 (100mg/L)(x) = (6mg/L)(0.25L) X = 0.15 L d 8ppm standard solution M1V1 = M2V2 (100mg/L)(x) = (8mg/L)(0.25L) X = 0.20 L e 10ppm standard solution M1V1 = M2V2 (100mg/L)(x) = (10mg/L)(0.25L) X = 0.25 L Result and Discussion: Based on the result from the experiment, the absorbance of light increased with increasing concentration of Lead. The calibration curve clearly shows the linear relationship between absorbance and concentration. From this curve the concentration of lead in anchovies was determine is 4.169 ppm. This experiment consist of preparing a series of standard solutions containing element to be determined (lead) and preparing solution of lead sample (anchovies) and then measuring the absorption of light by the atoms of the element when the solutions are aspirated into flame. A lamp containing lead emits light from excited lead atoms that produce the right mix wavelength to be absorbed by any lead atoms from the sample. the metal atoms in the cathode are excited into producing light with a certain emission spectra. A monochromator is used to select the specific wavelength of light which is absorbed by the sample and to exclude other wavelength.The amount of light absorbed is proportional to the number of lead atoms. The objective to determine the Lead in fish was achieved. References: 1 http://www. Conclusion: In this experiment.169 ppm. When a high voltage is applied across the anode and cathode. There are three steps involved in turning a liquid sample into an atomic gas which are desolvation. This contains a tungsten anode and a cylindrical hollow cathode made of the element to be determined. The lead concentration was calculated by comparing the amount the standard absorbs with the calibration curve.kau. The concentration of Lead from the experiment is 4.sa/files/130002/files/6785_aas.galbraith.com/spectroscopy.htm 2 http://www. The common source of light is a hollow cathode lamp. A calibration curve is constructed by running several sample of known lead concentration under the same conditions as the unknown.edu. This technique makes use of a flame to atomize the sample.pdf . The selected light by monochromator is directed onto a detector that is typically a photomultiplier tube. vaporations and volatilization. This will produce an electrical signal proportional to the light intensity. fish was used in determine the concentration of Lead. The selection of specific of light allows the determination of the selected element in the presence of others. Caffeine is also added to many foods. Tea removes fatigue. It also . tiredness and headache. The most common sources of caffeine are coffee. seeds or fruits. To quantify caffeine concentration in tea sample.Experiment 4: Background and Correction Method for the Determination of Caffeine in Tea Samples by using Ultraviolet Spectroscopy. Introduction: Caffeine is naturally occurring alkaloids which is found in the leaves. Objectives: 1. tea leaves. cocoa beans and others. 2. To familiarize with background correction method in UV Spectroscopy. drinks and particularly sodas for its mental stimulating effect. If a series of caffeine standards are analyze in this region of absorption and a Beer’s law is plot prepared. filter paper. Structure of Caffeine Instrumentation: 1. Instrumental model: Perkin Elmer-Lamba 3. hot plate. filter funnel Chemicals: 100ppm caffeine stock solution.increases the capacity of thinking and also helps to lowering the body temperature. Serial No:101 N 7070502 3.005 M NaOH. Caffeine absorbs radiation with wavelength around 260 nm. 0. pipette. Caffeine can be determined in foods or drinks by variety of methods. standard caffeine solutions Procedure: . But it can also cause a serious problem if taken in a large quantity. then the amount of caffeine in another substance can be determined. In this experiment. the concentration of caffeine was determined by using UV spectroscopy.5 2. Location: 305 Apparatus: Beaker 250ml. volumetric flask 100ppm. After the sample cold.1L) X = 0.1L) X = 0. Sample preparation: 2gm of dried tea sample was dissolved in 100ml of distilled water.10mL of the tea sample solution was transfer into a separating funnel.004 L c) 6ppm of standard caffeine solution M1V1 = M2V2 (100mg/L) (x) = (6mg/L) (0. 5ml of the diluted solution was transfer into another volumetric flask (100ml) and diluted again with distilled water. 0. 0.1L) X = 0. The mixture will separate into two aqueous layer at the bottom and organic layer at the upper layer. 1 ml of the extract was pipette into 5 different of 10ml volumetric flask. After that.4. Standard solution: a) 2ppm of standard caffeine solution M1V1 = M2V2 (100mg/L) (x) = (2mg/L) (0.6. the solution boiled using hot plate.002 L b) 4ppm of standard caffeine solution M1V1 = M2V2 (100mg/L) (x) = (4mg/L) (0. The distilled water added to the mark.2. the sample transfer into volumetric flask (100ppm) and diluted with distilled water. 20mL of CHCl 3 solution was added into the separating funnel and the mixture then shake. 0.8 and 1.006 L . 0.0mL of NaOH added in respective flasks. 028 g ∴ Dissolve about 0.008 L e) 10ppm of standard caffeine solution M1V1 = M2V2 (100mg/L) (x) = (10mg/L) (0.01 L Preparation of 0.d) 8ppm of standard caffeine solution M1V1 = M2V2 (100mg/L) (x) = (8mg/L) (0.25 L Mass = 0.005 M L 0. .09 g/mol 0.028 g of NaoH in distilled water.1L) X = 0.005 M of NaOH: 0.1L) X = 0.005mol L = mass molar mass volume = mass 22. Transfer the solution into 250 ml of volumetric flask and fill up with distilled water. . This amount typically corresponds to 4 cans of energy drink. 1998. The objective to . however the US Food and Drug Administration (FDA.6 to 9. Caffeine content in beverage drinks varies by brand from 10 to 60 mg of caffeine per serving (Violeta et al. Smith. Moderate caffeine consumption of 300 mg/day.45-20. 2010). cheap and highly sensitive for determination of caffeine content in tea sample. 2005). 2006) limits the maximum amount in carbonated beverages to 6 mg/oz (200 ppm). The average caffeine quantity in the tea sample was found to be ppm.28 mg/100 mL (NSDA. The caffeine content in the tea sample showed a minimum caffeine level which range from 8. is considered generally safe (Rogers and Dernoncourt. Conclusion: The methods develop on UV-vis spectroscopy is relatively easy.Result and Discussion: The standard linear calibration curve was obtained from standard solutions analysis and it showed a good linear relationship between absorbance and concentrations of the standard solutions. Therefore caffeine content allowed in soft drinks may be in the range between 30 and 72 mg/355 mL (12 oz) or 8. 1999).3 ppm. Riboflavin is strongly flurescent at pH 4-8. Riboflavin is a highly fluorescent molecule and it can be investigated using fluorescence spectroscopy. Under most circumstances.6 to 9. . 310-315 2.3 ppm. Excitation and fluorescence spectra will be obtained in 5% acetic acid solution to determine the wavelength of excitation and emission. 2) To familiarize with fluorescence spectroscopy.determine the caffeine content in tea sample was achieved. This vitamin is very important to our heart because it play a main role in allowing aerobic energy production to occur. Fluorescent is the emission of light by a compound after it has absorbed a particular wavelength of light. The caffeine content in tea sample obtain from the experiment is range from 8. References: 1. Journal of Food Chemistry 108 (2008). the emission of light will accur at longer wavelength than the light used to excite it. Journal of Food Science and Technology 6(2): 155-158. Objectives: 1) To quantify Riboflavin concentration in energy drink sample. 2014 Experiment 5: Determination of Riboflavin (vitamin B2) in Energy Drink. Introduction: Vitamin B2 also known as Riboflavin is a vital component of cofactors that support a flavoproteints. 0. volumetric flask.1 ppm by using the stock Riboflavin solution containing 100ppm of Riboflavin. A calibration Curve was plotted using the standard concentrations (x-axis) and their fluorescence values (y-axis). . the amount of riboflavin was determined in sample.Instrumentation: 1) Instrumentation model: Perkin Elmer-LS 55 2) Serial No: 85258 3) Location:305 Apparatus: Beaker 250 ml. From this curve. the solution was diluted with 1% (v/v) acetic acid solution. After that. 100ml (amber) and pipette Solutions to prepare: 1) Riboflavin standard solution (100ppm) 2) 500 ml 5% acetic acid Sample: Energy drink Procedure: A series of 5 standard solutions was prepared ranging from 0.02ppm. I. Preparation of 10ppm Riboflavin stock solution x 100ppm = 0. Preparation of 1% acetic acid M1V1 = M2V2 (10) V1 = (1) (100ml) V1 = 10 ml II. The solution was diluted in 100 ml volumetric flask with 1% acetic acid.15 L . Preparation of riboflavin standard solutions a) 2ppm standard solution M1V1 = M2V2 (100mg/L)(x) = (2mg/L)(0. III.1 L X = 10 mg ∴ 10 mg of weigh riboflavin was dissolve with 1% of acetic acid.25L) X = 0.25L) X = 0.25L) X = 0.01 L c) 6ppm standard solution M1V1 = M2V2 (100mg/L)(x) = (6mg/L)(0.005 L b) 4ppm standard solution M1V1 = M2V2 (100mg/L)(x) = (4mg/L)(0. 25L) X = 0.25L) X = 0.d) 8ppm standard solution M1V1 = M2V2 (100mg/L)(x) = (8mg/L)(0.20 L e) 10ppm standard solution M1V1 = M2V2 (100mg/L)(x) = (10mg/L)(0.25 L . The fluorometers and spectrofluorometers are composed of a light source. The magnitude of the output signal in fluorescence measurement and for that matter the sensitivity of the method is directly proportional to the radiant power of the source. One of the methods to cancel the effects of interfering substance involves the use of aluminum foil to cover the flask that used to prepare standards and samples. The riboflavin was extracted into solution first and followed by the assessment of its fluorescence. Some precautions step should be taken during conducting the experiment. There are many types of sources such as low-mercury lamp. high-pressure xenon arc lamp. Analysis of riboflavin by fluorometric method is made possible for the reason that riboflavin fluoresces strongly when exposed to light of wavelength in the range of 440 to 500 nm and the intensity of the fluorescence is proportional to the concentration of riboflavin in the solution examined.Result and Discussion: Fluorescence spectroscopy is a type of optical spectroscopy which analyzes fluorescence from a sample. This method is fairly straightforward in the absence of interference from fluorescing impurities. filters and monochromators. cells and cell compartment and a computer or electronic data system. . Blue light-emitting diodes (LEDs) and lasers. tranducers. The sources provide the excitation radiation for the sample. Conclusion: The objective to determine the concentration of riboflavin in energy drink was achieved. References: 1. and with a correlation coefficient of 0.com/innovate/monitoring-vitamin-b2-in-energy-drinks/ .etsu.vernier.0. The regression line was found to follow the equation: Y=359.cgi?article=3352&context=etd 2.89x + 0.9982. http://www. http://dc.edu/cgi/viewcontent. infection and arthritis. Instrumentation: . reduce fever. To determine aspirin (acetylsalicylic acid). For this experiment we use solid sample. FTIR is instrument to identifying types of chemical bond or functional groups. it also can prevent blood from clotting. The wavelength of light absorbed is show the characteristic of the chemical bond. The chemical bonds can ce determine by interpreting the infrared absorption spectrum. KBr is transparent to infrared light. Solid samples can be milled with potassium bromide (KBr) to form fine powder. Besides. Acetylsalicylic acid is one of the oldest analgesics substances. the spectrum of an unknown can be identified by comparison to the library of known compound. To understand and compare spectrum obtained from FTIR Introduction: Fourier Transform Infrared (FTIR) is most useful for identifying chemicals that are either organic or inorganic. It can be utilize to quantitate some components of an unknown mixture and can be applied to the analysis of solid. Aspirin is used to relieve pain. Samples for FTIR can be prepared in number of ways. liquid and gases. 2. relieve discomfort caused by medical problem including headaches. For most common materials. phenacetin and caffeine content in APC tablet. redness and swelling. This powder is then compressed into a thin pellet which can be analyzed. It is also used to prevent the risk of second heart attack or stroke.Experiment 1: Analysis of Aspirin in Commercial APC Tablet FTIR Spectroscopy Objectives: 1. The unit tilt back. The mixture was scrap and heap in the center of the mortar and grind again for 1 minute.010 g of sample was grind in agate mortar using pestle. The unit tilt back in order to hold the die set from falling off. The collar must stay in place. The die set lift carefully by holding the lower anvil. Method: 1) Mixture of sample and KBr The agate mortar and pestle was removed from desiccators. Chemicals: KBr. Location: 306 / 307 Apparatus: Mortar and pestle. sample. 2) KB pellets One fourth of the KBr mixture was taking into the collar of the hand press. Serial No: 55705 / ZH042703 3. After the handle closed. the dial pressure rotated until the upper ram of the hand press slightly touches the upper anvil on the die assembly. The mixture compress slowly while closing the handle in 2 minutes. About 0.8 g of KBr was added into the sample powder and mix them using a pestle.Spectrum One (FTIR) b) Bruker 300 UltraShelid (NMR) 2. Instrument model: a) Pelkin Elmer. Result and discussion: . After the handle open.1. the pressure dial rotated clockwise in one half turn. The anvil placed along with the loger die pin to make sure it comes into contact with samples. 0. the handle open and the die set remove from the unit carefully. The handle of the hand press slowly open and the die set insert into the hand press. wavenumber. there is no significant difference in the fingerprinting between spectra obtained from prepared KBr disk and the standard. The aromatic compound gives absorption peak at 870 cm-1 and 735 cm-1. The peaks in 2800. Molecules can vibrate in a variety of ways. The strong peak around 1710-1780 cm-1 is consistent with this since it could arise from the carbonyl group of carboxylic acid. broad absorbance in the 2500-3600 cm -1 region suggests a hydroxyl group arising from a carboxylic acid. In the structure of acetylsalicylic acid. There bonds can vibrate with stretch motion or bend motion. The movement of each ball toward or aways from the other ball along the line of the spring represents a stretching . The position of a absorption band (peak) in an spectrum is specified in unit of wavenumbers (ṽ).3000 cm-1 region suggest stretching of the C-H bonds of alkyl group either CH2 or CH3. The larger the wavenumbers. the bond vibration energies vary as moved horizontally on the graph.Based on the spectrum obtained from the experiment. Any frequencies absorbed by the spectrum will be appear by the different. Since an IR spectrum is a plot of % transmittance vs. The absorption peak at 3600 cm -1 – 2500 cm-1 arises from the stretching of carboxylic acids group of acetylsalicylic acid. there is aromatic compound. Wavenumbers are reciprocal of wavelength when wavelength is expressed in centimeters and therefore gives the number of wave cycles per centimeters. The strong. The IR spectra contain information about the structures of compounds. An infrared spectrometer operates by passing a beam of IR radiation through a sample and comparing the radiation transmitted through the sample with that transmitted in the absence of the sample. the higher is frequency of the bond absorption. wcaslab.chem. Stretching can either be symmetric or asymmetric. http://www. FTIR spectroscopy was used to determine the spectrum of acetylsalicylic acid in KBr.vibration. it shows that there is no significant difference.ucla.htm 2. http://www. References: 1. The objective of this experiment was achieved. By comparing to the standard spectrum.edu/harding/notes/notes_14C_IR. While a molecule with three or more atoms can experience a bendind vibration.com/tech/tbftir. Conclusion: In the experiment.pdf . Experiment 2: Determination of Cr2+ and Cd2+ in plant tissue samples using Atomic Absorption Spectrometry (AAS) Objectives: 1. The amount of energy absorb will increase as the number of atoms selected element in the light path increases. . The concentration unknown sample can be determined by measuring the amount of light they absorb. Atomic absorption occurs when atom at ground state absorb energy in the form of light of a specific wavelength and is elevated to an excited state. This instrument requires a primary light source. monitoring blood sugar levels and helps to stabilize blood sugar. The relationship between the amount of light absorbed and the concentration of analytes present in known standards was used to determine unknown sample concentration by measuring the amount of light they absorb. Small amounts of Cadmium concentration is soil will shortening the shoot axis and intensive yellowing of the older leaves. To familiarize with spiking technique in unknown concentration determination Introduction: Atomic absorption spectrometry (AAS) is an analytical technique that measures the concentration on elements. Chromiun has immense health benefits and must taken in right quantity. an atom source which is a manochromator. This function to isolate the specific wavelength of light to be measured. To compare data obtain from AAS and ICP 3. a detector to measure the light accurately. To determine Cr2+ and Cd2+ content in plant tissue samples 2. The light source used is hollow cathode lamp (HCL) or electrodelless discharge lamp (EDL). It helps metabolize carbohydrates. electronics to process data signal and data display. The objective of this experiment is to determine the Chromiun (Cr2+) and Cadminum (Cd2+) content in plant tissue. It’s very sensitive because it can measure down to parts per billion of a gram (ɥgdm -3) in a sample. Cadmium is non essential metal that effects plants growth and development. 1L) X = 0. Instrument model : Perkin Elmer-FIMS 400 2.5 g to 1. Procedures: 1. H2O2.Instrumentation: 1. The samples were heat on a hot plate about 20 minutes. Location: 305 Apparatus: Beaker250ml. Three portions of the samples weigh ranging from 0. Preparation of Cr2+ standard solution a) 1ppm standard solution M1V1 = M2V2 (1000mg/L)(x) = (1mg/L) (0. HNO3. the solution was added with 1 ml of H2O2 drop by drop and the precipitate formed. 7 ml of concentrated HNO3 added into each vessel. filter paper. Sample The plant sample was cut into small pieces and about 50 g of the sample put in oven to dry for 24 hours. volumetric flask 250ml. The solution was diluted into 100 ml of volumetric flask and make up with deionised water. Standard preparation I.0 g accurately. pipette Chemicals: 100ppm Cd2+ and Cr2+ standard solution. Serial No: A 40158010802 3. filter funnel. 2.0001 L b) 2ppm standard solution M1V1 = M2V2 . The solution was filtered using a filter funnel equipped with filter paper. 0004 L e) 5ppm standard solution M1V1 = M2V2 (1000mg/L)(x) = (5mg/L) (0.(1000mg/L)(x) = (2mg/L) (0. Preparation of Cd2+ standard solution a) 0.2mg/L) (100mL) X = 0.08 mL e) 1.1L) X = 0.6ppm standard solution M1V1 = M2V2 (1000mg/L)(x) = (0.0003 L d) 4ppm standard solution M1V1 = M2V2 (1000mg/L)(x) = (4mg/L) (0.1L) X = 0.6mg/L) (100L) X = 0.4ppm standard solution M1V1 = M2V2 (1000mg/mL)(x) = (0.0002 L c) 3ppm standard solution M1V1 = M2V2 (1000mg/L)(x) = (3mg/L) (0.02 ml b) 0.1L) X = 0.8mg/L) (100mL) X = 0.0ppm standard solution .4mg/L) (100L) X = 0.0005 L II.06 mL d) 0.1L) X = 0.04 mL c) 0.2ppm standard solution M1V1 = M2V2 (1000mg/mL)(x) = (0.8ppm standard solution M1V1 = M2V2 (1000mg/L)(x) = (0. Atomic Absorption Spectroscopy in analytical is a technique for determining the concentration of particular metal element within a sample. The calibration curve clearly shows the linear relationship between absorbance and concentration.261 ppm while for Chromium was 1.623 ppm. In this experiment. There are three steps involved in turning a liquid sample into atomic gas which . environment and vessel wall.0mg/L) (100mL) X = 0. the absorbance of light increased with increasing concentration of Cadmium and Chromium. The technique makes use of a flame to atomize the sample but other atomizers such as graphite furnace are also used. The sample was covered with aluminium foil in this experiment.M1V1 = M2V2 (1000mgm/L)(x) = (1. wet digestion method was used for sample preparation. The use of closed system is completely isolated from the surroundings may help to prevent both contamination and sample loss. From this curve the concentration of Cadmium in plant tissue was determine is 1.10 mL Result and discussion: Based on the result from the experiment. The various acid and flux treatment was carried out in high temperature to help to minimize contamination of sample with substance in the air. This will produce an electrical signal proportional to the light intensity.com/doc/88715301/CHM-580-EXP-AAS 2.galbraith. References: 1. A monochromator is used to select the specific wavelength of light which is absorbed by the sample and to exclude other wavelength. http://www. spinach was used in determination of Cadmiun and Chromiun in plant tissue.623 ppm.htm . When a high voltage is applied across the anode and cathode. The selection of specific of light allows the determination of the selected element in the presence of others. The objective to determine the Cadmium and Chromiun in plant tissue was achieved. The common source of light is a hollow cathode lamp. The concentration of Cadmium in spinach is 261 ppm while for Chromium was 1. Conclusion: In this experiment. vaporation and volatilization. http://www.are desolvation.scribd.com/spectroscopy. This contains a tungsten anode and a cylindrical hollow cathode made of the element to be determined. The selected light by monochromator is directed onto a detector that is typically a photomultiplier tube. the metal atoms in the cathode are excited into producing light with a certain emission spectra. UNIVERSITI TEKNOLOGI MARA PERLIS ARAU CAMPUS FACULTY OF APPLIED CHEMISTRY CHM 580 SPECTROCHEMICAL METHODS OF ANALYSIS EXPERIMENT 1: . Analysis of Aspirin in Commercial APC Tablet FTIR Spectroscopy Name: Nur Farah Hanani Binti Mamat Group: ASB4Bg Matric no: 2012221848 Due date: 2 April 2014 UNIVERSITI TEKNOLOGI MARA PERLIS ARAU CAMPUS FACULTY OF APPLIED CHEMISTRY CHM 580 SPECTROCHEMICAL METHODS OF ANALYSIS . EXPERIMENT 2: Determination of Cr2+ and Cd2+ in plant tissue samples using Atomic Absorption Spectrometry (AAS) Name: Nur Farah Hanani Binti Mamat Group: ASB4Bg Matric no: 2012221848 Due date: 2 April 2014 UNIVERSITI TEKNOLOGI MARA PERLIS ARAU CAMPUS FACULTY OF APPLIED CHEMISTRY CHM 580 SPECTROCHEMICAL METHODS OF ANALYSIS EXPERIMENT 3: . Determination of Lead in Anchovies by Cold Vapors Generation Atomic Absorption Spectrometry Name: Nur Farah Hanani Binti Mamat Group: ASB4Bg Matric no: 2012221848 Due date: 2 April 2014 UNIVERSITI TEKNOLOGI MARA PERLIS ARAU CAMPUS FACULTY OF APPLIED CHEMISTRY CHM 580 SPECTROCHEMICAL METHODS OF ANALYSIS EXPERIMENT 4: . Background and Correction Method for the Determination of Caffeine in Tea Samples by using Ultraviolet Spectroscopy Name: Nur Farah Hanani Binti Mamat Group: ASB4Bg Matric no: 2012221848 Due date: 2 April 2014 UNIVERSITI TEKNOLOGI MARA PERLIS ARAU CAMPUS FACULTY OF APPLIED CHEMISTRY CHM 580 SPECTROCHEMICAL METHODS OF ANALYSIS . EXPERIMENT 5: Determination of Riboflavin (vitamin B2) in Energy Drink Name: Nur Farah Hanani Binti Mamat Group: ASB4Bg Matric no: 2012221848 Due date: 2 April 2014 .