C5H4 C10H8 C2H3 None of these chem 121. View Calculation.pdf from CHM chm1321 at University of Ottawa. Determine the percent by mass of each component on your mixture using the following formula: mass of component A % of component A x 100% mass of original sample ring stand Naphthalene (C ioH 8) is employed in the mass transfer experiments because of some of its properties, such as the fact that it sublimes at room temperature, its low toxicity, and its good casting and machining properties. Many organic solvents, like ether and dichloromethane . 2. Given: mass of sample and mass of combustion products After the extraction and recrystallization, 0.73g of benzoic acid and 0.502g of naphthalene were recovered. Calculate the percent composition for each of the components. A student completed the experiment but found that the total amount of material recovered weighed more than the original sample. If the mass of the BaSO4 precipitate formed is 0.4105 g, what is the percent by mass of Ba in the original unknown compound? Naphthalene conversion (naphthalene hydrogenated to tetralin, octalins and decalins) varied from 4 to 96%. 1,2 It is an insecticide that is also used as a repellent. Experiment: We obtained 3.1 grams of the benzoic acid, aniline, and naphthalene mixture. The reaction taking place is. What are the empirical and molecular formulas of the compound? The mass of the solution is the sum of . A student completed the experiment but found that the total amount of material recovered weighed more than the original sample. A 10 ml volume of a synthetic sample was extracted with 10 ml of dichloromethane in a 30 ml vial; the layers were allowed to separate.Prior to SPE work, 2-4 ml of the organic layer was removed and stored in a sealed glass vial at 4 C.The extraction of a river water sample was carried out essentially according to . The aim of this study was to evaluate the impact of biofield energy treatment on the isotopic abundance of 13 C/ 12 C or 2 H/ 1 H and 18 O/ 16 O in naphthalene and 2-naphthol using gas chromatography-mass spectrometry (GC-MS). Lab 4 Separation of Benzoic Acid, 3-Nitroaniline, and Naphthalene Objectives Separate organic compounds based on functional groups Use pH changes to separate compounds Background Separations of Immiscible Liquids Throughout organic experiments, multiple different solvents get used, such as a variety of organic solvents and water. The sample should be transferred to a beaker. Previous studies using Cyp2abfgs-null (lacking all genes of the Cyp2a, 2b, 2f, 2g, and 2s subfamilies), CYP2A13/2F1-humanized, and liver-Cpr-null (LCN) mice showed that although hepatic cytochrome P450 (P450) enzymes are essential for systemic clearance of inhaled naphthalene (a possible human carcinogen), both hepatic and extrahepatic P450 enzymes may contribute to naphthalene-induced lung . Calculation % by mass of naphthalene in original sample: (0.632 g/ 2.039 g) x 100 = 30.9955861% % by mass of 3-nitroaniline in original A 0.500 g sample of naphthalene (C10H8) is burned in a bomb calorimeter containing 650 . A 3.000-mg sample of naphthalene burns to give 10.3 mg of CO 2. 40% CaCO3. What was the % by mass of CaCO3 in the original sample? and anthracene, c14H10 is dissolveed in 20.0g of benzene, C6H6. A 1.00 g sample of naphthalene (C10H8) contains 0.562 g of hydrogen. Attempt to get samples within 100 mg of the weight of the original sample. TALANTA Volume 85, Issue 1, Pages 345 . Determine the composition (mass percentage) of naphthalene-anthracene mixture?" Dolomitic limestone is a mixture of CaCO3 and MgCO3. Mass of the original sample of mixture (g) 1.537 Mass of recovered naphthalene (9) 0.461 Mass of recovered 3-nitroaniline (g) 0.507 Mass of recovered benzoic acid (g) 0.507 (12pts) Calculations (3/3pts) % by mass of naphthalene in original sample 30.0 V (0/3pts) % by mass of 3-nitroaniline in original sample 30.0 (-3 pts) Incorrect. The freezing point of the solution was determined and found equal to 78.1C. This paper is intended to be an introductory text on the naphthalene sublimation technique. v, Density of naphthalene in . Sample Exercise 13.3 Converting Units of Temperature Solution (a) Analyze We are given the number of grams of solute (13.5 g) and the number of grams of solvent (0.100 kg = 100 g). Record the sample weight data in your notebook in proper format. This content was COPIED from BrainMass.com - View the original, and get the already-completed solution here! Vapor pressure measurements can be used to find the mass of naphthalene transferred from the sample to a stream of gas passed over . The mass flux of naphthalene was substantially reduced by the MGPC . . Determine its empirical and molecular formulas. The molecular mass of naphthalene = 128.17 gm/mol The molecular mass of 3-nitro aniline = 1. a) calculate % by mass of naphthalene, 3-nitroaniline and benzoic acid in original sample 1. b) A: 1)a. All operations required to test a sample or to standardize the 1341 Plain Jacket Calorimeter should proceed step-wise in the following manner: 1. 2.5. The use of mass spectrometry (MS) is becoming widespread and rather routine in all levels of industry, government, and academia. When a 1.00 grams sampleof this limestone is decomposed by heating, 268 cm3 of CO2 (g) is produced measured at 750. torr and 20C. Homework Statement. It is the simplest polycyclic aromatic hydrocarbon, and is a white crystalline solid with a characteristic odor that is detectable at concentrations as low as 0.08 ppm by mass. Need some help here: 1. When this sample is dissolved . 6-C . All samples showed concentrations above the limit of quantification, except for samples 2 and 3 of the outdoor air. Using the same sample, now with the unknown in it: melt and solidify the mixture, recording a second set of data with An 887.0 mg sample of a mixture containing only NaCl and KCl is dissolved in water, and excess AgNO3 is added to yield 1.913 g of AgCl. The naphthalene yield was much lower, . How much heat is needed to convert 10g ice to 10g water vapor? The peas were freeze dried and the . . The reaction was carried out in a slurry batch reactor using goethite as the Fe (III) source. . Weigh a clean and dry 250-mL beaker (Beaker #2). 17 Naphthalene is considered low in toxicity by . Record exact mass. Each step produced an organic layer as well as an aqueous layer. The vapor pressure of pure hexane at . From this we must calculate the mass percentage of solute. Fill the calorimeter bucket by first taring the dry bucket on a solution or trip balance . Discussion: During World War 2, one of the major problems scientists faced . Follow your professors instructions. Mass of original sample _____ 4. Calculations Total mass of original mixture- 1.02g Mass of sand: 0.65 g Mass of salt- 0.233g Mass of calcium carbonate: 0.137g Calculate the mass of NaHCO3 present in the original mixture. Subtract to find the mass of NaCl in the original mixture. Determine the empirical formula of naphthalene. Complete combustion of a 20.10 mg sample of naphthalene in oxygen yielded 69.00 mg of CO 2 and 11.30 mg of H 2 O. Given: mass of sample and mass of combustion products Quantitative detection of trace perfluorinated compounds in environmental water samples by Matrix-assisted Laser Desorption/Ionization-Time of Flight Mass Spectrometry with 1,8-bis(tetramethylguanidino)-naphthalene as matrix. Determine its empirical formula. If the original mass of the evaporating dish and the hydrate was 21.71 g, and the mass of the evaporating dish alone was 1.315 g, what is the mass of water removed from the sample by heating? To recrystallize the naphthalene, heat about 50 mL of the 3:1 methanol:water mixture almost to the boiling point on a steam bath (see p. 78 in LTOC). Given: mass of sample and mass of combustion products 7. Created by Sal Khan. Q: % by mass of naphthalene in original sample % by mass of 3-nitroaniline in original sample % by mass A: Given mass of the original sample of mixture (g)= 1.547 mass of recovered naphthalene (g) = 0.511 Elemental analysis can be used to determine the amounts of substances in a mixture. A solution contains naphthalene (C10H8) dissolved in hexane (C6H14) at a concentration of 14.52 % naphthalene by mass.Calculate the vapor pressure at 25 degrees C of hexane above the solution. A simple and sensitive method for the simultaneous analysis of naphthalene, fluorene, and anthracene in whole blood was developed using headspace-solid-phase microextraction (SPME) and GC/MS. You dissolve 0.4500 g of impure potassium chloride in water and add an excess of silver nitrate. Complete combustion of a 20.10 mg sample of naphthalene in oxygen yielded 69.00 mg of CO 2 and 11.30 mg of H 2 O. 3. Determine the empirical formula of naphthalene. 205M. To the sample, add approximately 50 mL of laboratory water and stir continuously with a glass stirring rod for about two minutes. Data Collection Mass of the original sample of mixture (g) 1.558 Mass of recovered naphthalene (g) 0.483 Mass of recovered 3-nitroaniline (g) 0.499 Mass of recovered benzoic acid (g) 0.467 Calculations: a. Spot 3: A few crystals of naphthalene product in 1 mL ethyl acetate. Determine the empirical formula of naphthalene. Naphthalene (NAP) has received particular attention due to its impact on the environment and human health, mandating its removal from water systems. Naphthalene is an organic compound with formula C 10 H 8.It is the simplest polycyclic aromatic hydrocarbon, and is a white crystalline solid with a characteristic odor that is detectable at concentrations as low as 0.08 ppm by mass. A 0.573g sample of a nonvolatile solute is added to 15.6g of napthalene and the mixture warmed until melted. tt. [13] As an aromatic hydrocarbon, naphthalene's structure consists of a fused pair of benzene rings. Rautanen, . Not only was it evident that the impurities had been removed due to the color of the resultant Naphthalene, but it could also be seen in the difference between the starting mass and the mass retrieved. The percentage yield for this experiment was 88.314%. Freezing point depression provides a convenient way to determine the molar mass of an unknown substance. In this work, the abatement of NAP in the aqueous phase was achieved using persulfate (PS) activated by Fe (III) and monochromatic LED light at a natural pH. 2) Calculate the mass percent of NaHCO3 in the uknown mixture . Mass of dish #1 plus dry SiO . I need the correct answer please Mass of the original sample of mixture (g) 1.537 Mass of recovered naphthalene (9) 0.461 Mass of recovered 3-nitroaniline (g) 0.507 Mass of recovered benzoic acid (g) Q&A. Chemistry questions and answers. M 00 Local naphthalene mass flux, kg/s-m2. Naphthalene, the active ingredient in one variety of mothballs, is an organic compound that contains carbon and hydrogen only. 7. chemistry. Linear regressions passing the original point were applied for all the sorbents under the range of naphthalene concentration (1 ppm-40 ppm). Coupled with chromatographic methods, this powerful instrumental technique can be used to elucidate the composition of a complex sample and definitively identify constituents while offering the benefits of high-precision quantitative analysis and low detection limits. The highest concentrations . Methods of pesticide analyses have been largely driven by the food industry [1-3].In their comprehensive paper of 2000, Filion et al. A package of freshly picked sweet peas has a mass of 454 g (1 lb.). E. Percent by Mass. Spot 2: The sample of liquid mixture taken before the rotary evaporation/or re-crystallization. A 3.000-mg sample of naphthalene burns to give 10.3 mg of CO2. Naphthalene, the active ingredient in one variety of mothballs, is an organic compound that contains carbon and hydrogen only. Using the technique of weighing by difference, weigh out a 0.7 g sample of NaCl. Sample ID #74 Mass of Vial with sample 12.00g Mass of Empty Vial 10.00g Mass of Sample 2.00g Mass of 100 mL round-bottom flask 67 . Samples 1 to 3 were collected at ecological park sites and are thus close to the background concentrations of naphthalene for urban and suburban centers, which can vary from 0.001 to 1 g/m 3, . Z Local sublimation depth, m. t Time duration of the test, s. m Difference in weights of the specimen, g. As Area of naphthalene surface, m 2. -naphthalene as matrix Authors. Naphthalene | C10H8 | CID 931 - structure, chemical names, physical and chemical properties, classification, patents, literature, biological activities, safety . Naphthalene, the active ingredient in one variety of mothballs, is an organic compound that contains carbon and hydrogen only. Webinars; Posters; Hubs; . 19 Researchers determined an LD 50 of 353.6 mg/kg for female CD-1 mice based on an 8-day oral exposure. A.O.I. For example, if elemental analysis tells us that a potassium supplement contains 22% K by mass, and we know that the K is present as KCl, we can calculate the grams of KCl in the supplement. . Given: mass of sample and mass of combustion products Mass of the original sample of mixture (g) 1.547 Mass of recovered naphthalene (g) 0.511 Mass of recovered 3-nitroaniline (g) 0.480 Mass of recovered benzoic acid (g) 0.472 % by mass of naphthalene in original sample % by mass of 3-nitroaniline in original sample % by mass of benzoic acid in original sample Total percent recovered. b. Complete combustion of a 20.10 mg sample of naphthalene in oxygen yielded 69.00 mg of CO 2 and 11.30 mg of H 2 O. Thirtynine healthy and non-smoking male employees with either moderate (n = 22) or high (n = 17) exposure to naphthalene were compared to 22 male employees from the same plants with no or only rare exposure to naphthalene. 4 The Chemical Abstracts Service (CAS) registry number is 91-20-3. The original mass of the 50:50 mixture measured was 2.042g, and assuming it is truly 50:50, it can be anticipated that the mass of both naphthalene and benzoic acid was 1.021g. C_10H_8 Assuming that is a mass amount, divide each proportion by the atomic weight of the component. . % by mass of 3-nitroaniline in original sample. A 1.60 g sample of a mixture of naphthalene, C10H8, and anthracene, C14H10, is dissolved in 20.0 g benzene, C6H6. Record the mass and number or letter of the unknown on the data sheet and place the unknown in the test tube containing your original sample of naphthalene. c. % by mass of benzoic acid in original sample. [] screened fruit and vegetable samples for 251 known pesticides by extracting pulp with solvent before clean-up on solid phase extraction cartridges.The final extract was pre-concentrated and analysed by GC-MS or LC-fluorescence. Naphthalene is soluble in methanol and insoluble in water. SPQ2.B (LO) , SPQ2.B.1 (EK) Transcript. What are the empirical and molecular formulas of the compound? What is the mass percent of carbon in the compound . A 3.000-mg sample of naphthalene burns to give 10.3 mg of CO 2. Do not stir at this time. Dermal. Determine the empirical formula of naphthalene. Determine the empirical formula of naphthalene. mass of oxygen = mass of sample - (mass of carbon plus mass of hydrogen) Since we burned 1.00 g of our sample, it follows that we can calculate the mass of oxygen by subtracting the combined masses of C and O from the mass of sample. Calculate the change in mass for each sample. 82) A sample of 0.6760 g of an unknown compound containing barium ions (Ba2+) is dissolved in water and treated with excess Na2SO4. T f,solution T f,solvent = T f = K f . 1) Will weighing the collected (scraped) naphthalene Calculate the percent by mass of KCl in the original sample. Local and average mass transfer coefficient, m/s. By the end, we should have had the separated benzoic acid, aniline, and naphthalene. Pure Benzene freezes at 5.51C and has a Kf = 5.12C kg/mol. Naphthalene, the active ingredient in one variety of mothballs, is an organic compound that contains carbon and hydrogen only. "A 1.60 g sample of a mixture of naphtalene, C10H8. Naphthalene, the active ingredient in one variety of mothballs, is an organic compound that contains carbon and hydrogen only. The makeup of that 88.314% is divided between naphthalene at 4.550%, NaCl at 39.368%, and sea sand at 44.397%. Krause, in Studies in Surface Science and Catalysis, 2001 3.3 Naphthalene and Tetralin Conversion. It will dissolve in a hot mixture of 3:1 methanol:water but is less soluble when this mixture is cold. Iodine (I2), naphthalene (C10H8, mothballs), ammonium chloride (NH4Cl) and dry ice (solid CO2) are some substances which sublime. A 1.60 g sample of a mixture of naphthalene, C10H8, and anthracene, C14H10, is dissolved in 20.0 g benzene, C6H6. Determine its empirical and molecular formulas. % by mass of naphthalene in original sample. Let mixture stand for a few minutes to allow the undissolved components settle to the bottom of the mixture. The naphthalene was the scraped into a vial with no cap and left to stand and dry for a week before determining the melting point. When the reaction ends, pour out the water and weighed the mass of the mixture on the digital scale. Naphthalene, the active ingredient in one variety of mothballs, is an organic compound that contains carbon and hydrogen only. An additional experiment carried out with very low catalyst loading led to a low . The percent composition for each component is: 16.5g carbohydrates / 130.g x 100 = 12.7% carbohydrates, 9.7g sugar / 130.g peas x 100 = 7.5% sugars, 8.1g dietary fiber / 130.g peas x 100 = 6.2% dietary fibers, 4.4g protein / 130.g peas x 100 = 3.4% protein, The peas were freeze dried and the . Subtract this number and the mass of the salt from the original total mass will help you find the mass of the sand. A student found that the mass of the naphthalene collected was less than the mass determined by difference. As an aromatic hydrocarbon, naphthalene's structure consists of a fused pair of benzene rings. The mass of water evaporated is obtained by subtracting the mass of the anhydrous solid from the mass of the original hydrate (\ref{3}): . . r Radial coordinate, m. Sh;Sh Local and average Sherwood number. the purity of the naphthalene fraction changes over the course of the extraction. A substance is classified as efflorescent if its mass decreases by 0.005 g or more; and it is classified as hygroscopic if its mass increases by 0.005 g or more. That is: mass of oxygen = 1.00 g - (0.409 g + 0.046 g) = 1.00 g - 0.455 g = 0.545 g. Naphthalene | C10H8 | CID 931 - structure, chemical names, physical and chemical properties, classification, patents, literature, biological activities, safety . Upload a picture of your drawn separation scheme for benzoic acid from the . The dermal LD 50 was determined to be greater than 2000 mg/kg in rabbits. Methods. A 0.5 g whole blood sample, 5 microL naphthalene, fluorene, and anthracene (50 microg/mL) as spiked standards, and 0.5 mL sodium hydroxide were placed . CHROMATOGRAPHY is the process of separating a mixture by the . These data were obtained by passing air over a sample of the sub-stance in a tube. 2. and potassium chloride (KCl) has a total mass of 4.000g. Complete combustion of a 20.10 mg sample of naphthalene in oxygen yielded 69.00 mg of CO 2 and 11.30 mg of H 2 O. A 1.60 g sample of a mixture of naphthalene, C10H8, and anthracene, C14H10, is dissolved in 20.0 g benzene, C6H6. 20. Naphthalene is a bicyclic aromatic hydrocarbon derived from coal tar or crude oil.