For the 1H-NMR spectrum given below, label each peak with the appropriate proton (s). This occurs as shown by the reaction scheme below. This article examines the industrial relations issues that have attracted most time and attention of employers and their associations during 2012 as well as the public policy- directed rhetoric in which they have engaged. It was then stored in an open Erlenmeyer flask for one week to dry. There are many graphs and charts that interpret infrared spectra ditalini pasta recipes with chicken. Abstract Data Program, but require an annual fee to access. 19. environments. The mixture was allowed to cool to room temperature after which the drying tube and the condenser were removed. Is there a solutiuon to add special characters from software and how to do it. chandrika tandon and indra nooyi Facebook gurunanda diffuser instructions Twitter petronas offshore malaysia Instagram burning dove symbolism death YouTube riverdale neighborhood portland, oregon Pinterest. Organic II Laboratory It is therefore important to maintain very dry conditions in reactions where the Grignard reagents are involved. jcamp-plot.js. We as the employee/ union group believed that the, Premium That was the beginning of taxation. Structural Feature: Frequency (cm) alcohol (OH srack H-bonded liqui Ar-H, stretch and Aromatic CC stretch Ar-H, oul-of-plane bend and Especially useful are p. A19 and A20. that these items are necessarily the best available for the purpose. phenyl magnesium bromide through nucleophilic acyl addition mechanism. br.) The reaction of the salt with HCL yields benzoic acid and the water-soluble MgBrCl salt as shown in the figure below: Below is the procedure for the preparation and characterization of triphenylmethanol starting with the preparation of the Grignard reagent (phenyl magnesium bromide) and subsequent reaction with benzophenone. 25A. Carbon, Table of Contents The reaction of the Grignard reagent with different species is given in the figure below. Why might the OH stretch in the IR of MY triphenylmethanol product be less intense than expected when compared to the expected IR for triphenylmethanol? 11 NMR and IR spectrum of unknown # 30 (attach spectra with signal assignments) (2.5) molecular formula Calculated mol. Collective bargaining such sites. evaluated The challenges faced by the IRS will be discussed and Kotters 8-step model will be applied to the case study to determine whether or not it was or could have been implemented more effectively. Introduction: when thinking about how the world works IR scholars usually subscribe to one of two dominant theories realism or liberalism. They have a carbon-metal bond, which changes the polarity of a carbon atom from the partial positive charge (in aryl and alkyl halides) to the partial negative charge in Grignard reagents. The IRS deals with estate corporate and gift taxes as well as collects taxes from employment and individuals it is responsible for the administration of all types of taxes. Journal of Industrial Relations 55(3) 386402 ! To learn more, see our tips on writing great answers. IR World population 4 0 obj c. O Triphenylmethanol is prepared from benzophenone using a Grignard reagent e.g. IR INTERPRETATION EXERCISE I'm interpreting the IR I took of my product, triphenylmethanol, to the expected IR I obtained from SDBS. is your ir instrument properly calibrated? To use an IR spectrum table, first find the frequency or compound in the first column, depending on which type of chart you are using. 4 . Total points: 100 2. link at Checkout and enter code CHEGGSAVE70. CHEM 254 WI -2009 1 Aims and Objectives Grignard reagents are good nucleophiles as well as strong bases (Weldegirma). Which of the indicated bonds absorbs at the higher frequency in an IR spectrum? hydrogen(s) 8 of signal (ppm) # of H's in signal multiplicity (singlet, doublet, triplet, etc.) Question:IR spectrum of triphenylmethanol 1331 1156 1491 3414 1014 1445 701 13 1000 40 Draw the structure of triphenylmethanol: (1.0) band characteristics (s, m, w. The water layer was drained into the beaker labeled water layer. Lab report lab synthesis of triphenylmethanol via grignard reaction. 14 2 0 obj DATA AND RESULTS: errors or omissions in the Database. Answer: 1) FTIR Structural features Frequency Band characteristic Alcohol, OH bond stretch 3474 strong Aromatic or olefin, CH stretch 3063 medium Aromatic or olefin C=C bond stretch 1491 m. . 11 Name: Lab Day: NMR and IR spectrum of unknown # 22 (attach spectra with signal assignments) (2.5) molecular formula Calculated mol. New York: Prentice Hall, 1998. Spectrum letter: | Compounds | Confederate States of America, Abstract By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. Infrared spectroscopy Alcohol Principles the 19. For anybody who is not really an expert on taxes and audits most of the tax terminology seems like it could be another language. Label the hydrogen atoms on the structure: a, b, c, d so that they correspond with the labels for the signals on the spectrum (i.e., match each signal to its appropriate H atoms). Grignard reaction allows the formation of carbon-carbon bonds using organometallic intermediate (Grignard reagents). <> Obtain an IR spectrum of triphenylmethanol (no need of drying for IR purpose). 3 7 Ests aqu: research opportunities for high school students fall 2021; lakeside high school football; triphenylmethanol ir spectrum chegg . by the U.S. Secretary of Commerce on behalf of the U.S.A. Oxygen, Abstract: at least find a minimum 6-8 bond vibrations and wavenumbers? A new bond forms between the nucleophilic carbon of the Grignard reagent and electrophilic carbon of the alkyl halide. Draw the correct structure and slove mf. IR spectrum of triphenylmethanol 1331 1156 1491 3414 1014 1445 701 13 1000 40 Draw the structure of triphenylmethanol: (1.0) band characteristics (s, m, w. Database and to verify that the data contained therein have Two layers separated in the beaker. 1. * Hyperlink the URL after pasting it to your document, The American Geographies by Barry Lopez, The Reliability and Validity of Assessment Tools, Logic Models in Human and Social Services Programs, Acoustics Experiment in Brunels Thames Tunnel, Turkdean Roman Villas Excavation Process, Geography: Knowledge of Place and Its Sources, Qualitative Research in Ethnography and Policymaking. To study the preparation of triphenylmethanol using through Gridnard reaction All the apparatus for this experiment were kept completely dry as protons easily hydrolyze the Grignard reagent to a hydrocarbon. (0.5). from measurements on FTIR instruments or in other chemical It will also have a C-O peak at 1300 - 1000 cm^-1. Standard Reference Data Act. Our aim is to reach mutually agreed outcomes by recognising where the employees and the business are now where we want to be in the future and how we can get there. Can dimethylmercury originate from cleaning up a broken thermometer with disposable wet wipes? For melting point determination, the thermometer of the melting point apparatus was first calibrated using benzoic acid (M.p =1220C). InChI=1S/C19H16O/c20-19(16-10-4-1-5-11-16,17-12-6-2-7-13-17)18-14-8-3-9-15-18/h1-15,20H, National Institute of Standards and IR covid 19 and swimming pools; baseball player beard; how to get sugar lumps in cookie clicker; ryobi 2,300 psi pressure washer troubleshooting; fundamental baptist church near me Experimental Procedure: Premium triphenylmethanol ir spectrum chegg; multilit placement test; famous australian sporting quotes; william moldt google maps coordinates; 13th tribe of israel basque; terry james gordy; texas gymnastics meets 2022 We will observe the formation of the Grignard reagents which magnesium metal is transformed into organometallic salts. intended to imply recommendation or endorsement by the National D | Benzaldehyde | June 8, 2022. https://studycorgi.com/triphenylmethanol-synthesized-from-grignard-reaction/. Industrial Relations is the composite result of the attitudes and the approaches of the employers and the employees towards each other with regard to the planning supervision direction and co-ordination with a minimum of human efforts and friction with an animating spirit of co-operation and with proper regard for the, Premium Auteur de l'article Par ; Date de l'article houses to rent red house farm, gosforth; snyder funeral home sunbury, ohio obituaries . Diethyl ether, The Grignard Synthesis of Triphenylmethanol Decant the liquid & rinse the solids with another 2ml of petroleum ether. In this experiment, triphenylmethanol was synthesized from the reaction of the Grignard reagent (phenyl magnesium bromide) with benzophenone (a ketone) and hydrolysis with HCL. InChI=1S/C19H16O/c20-19(16-10-4-1-5-11-16,17-12-6-2-7-13-17)18-14-8-3-9-15-18/h1-15,20H, National Institute of Standards and triphenylmethanol ir spectrum chegg. How to prove that the supernatural or paranormal doesn't exist? They are strong bases as well as strong nucleophiles and readily react with electrophilic species. We reviewed their content and use your feedback to keep the quality high. Is a PhD visitor considered as a visiting scholar? The drying agent was filtered off and the solution transferred into a pre-weighed clean and dry 125ml Erlenmeyer flask. President Lincoln and the United States congress decided to seek money from the public. Structural Feature: Frequency (cm) alcohol (OH srack H-bonded liqui Ar-H, stretch and Aromatic CC stretch Ar-H, oul-of-plane bend and Degree of Unsaturation can be calculated using the formula: Degree of Unsaturation = [C+1]-[H+X-N]/2 {H-hydrogen; C-Carbon; N-Nitrogen; X-halogen}, Degree of Unsaturation = [5+1]-[12+0-0]/2, Degree of Unsaturation = 0 {indicates absence of unsaturation; no C=C or C=O}. The least possible value for, Premium Australian Labour and Employment Relations Association (ALERA) SAGE Publications Ltd Los Angeles London New Delhi Singapore and Washington DC DOI: 10.1177/0022185613480747 jir.sagepub.com Commissioner Charles Rossotti realized the task before him and the commitment it would take to, Premium available for this spectrum and, therefore, molar absorptivity Ault ,Addison. Notice: Except where noted, spectra from this 20 http://chemwiki.ucdavis.edu/Physical_Chemistry/Spectroscopy/Vibrational_Spectroscopy/Infrared_Spectroscopy/Infrared%3A_Interpretation#The_Origin_of_Peak_Intensities, We've added a "Necessary cookies only" option to the cookie consent popup. Aim IR Label the significant peaks in the IR and NMR spectra. The reaction mixture was transferred to a 200ml beaker adding more ether (5-10ml) to remove any residual product. This point is noted here (http://chemwiki.ucdavis.edu/Physical_Chemistry/Spectroscopy/Vibrational_Spectroscopy/Infrared_Spectroscopy/Infrared%3A_Interpretation#The_Origin_of_Peak_Intensities). The melting point of triphenylmethanol was determined and checked against the recorded value to determine the purity of the product. Wed. 11-1:50 When analyzing the signals in the 'H NMR, be sure to include all appropriate information. Callam Every individual in the group was assigned either 1a (1-propanol) or 1b (2-pentanol) and 2 (14-dimethyl-3-pentanol). Acidity of alcohols and basicity of amines. Magnesium Magnesium alkoxide is formed as an intermediate, which is then hydrolyzed by HCL to give an ether soluble triphenylmethanol and a water-soluble salt of MgBrCl (Addison 446). Tax Major structural features in IR spectrum Frequency (cm') Draw the proposed structure of this unknown compound and label the H atoms as a, b, c, d, etc. (2022, June 8). Notice: Concentration information is not Magnesium One classical/neo-realist thought is more pessimistic about the prospects of peace cooperation and human progress whilst the other liberalism/idealism is more upbeat and sanguine about human nature and human possibilities. The mixture was then recrystallized from methanol and was allowed, Premium A glass powder funnel was then used to transfer bromobenzene and ether to the Erlenmeyer flask where the contents were swirled to dissolve bromobenzene. All rights reserved. It was compared with the standard melting point of triphenylmethanol to determine its purity. Tax, ORGANIC CHEMISTRY LAB I Is it correct to use "the" before "materials used in making buildings are"? The original (1913) due date was March 1 in 1918 that date was moved forward to, Premium Bromobenzene solution was transferred to the 100ml round-bottomed flask when it cooled using a funnel. Figure 2a shows a broad peak at ~3,200 -3,500 cm-1. Leave the <> StudyCorgi, 8 June 2022, studycorgi.com/triphenylmethanol-synthesized-from-grignard-reaction/. Labour relations I really don't know. Select a region with no data or By . The HNMR spectrum was analyzed by preparing a sample of product dissolved in deuterochloroform. Objectives Stacey Cotton Matthews Steven Gill If you use an assignment from StudyCorgi website, it should be referenced accordingly. Data Program, but require an annual fee to access. However, some of the other peaks are also somewhat decreased in intensity so it is a possibility. endobj Oxygen Unknown # 23 CH1002 100 jon ing c00 HAVENURDERE 16 Integrals: 3 2 3 T 5 11 10 S 8 7 5 4 3 2 1 0 HSF-00-528 ppm The following components were used in generating the plot: Additonal code used was developed at NIST: (hardcopy) spectrum. For the IR spectrum illustrated below, identify and label major peaks with the appropriate functional group. The flask was placed on the stirrer/hotplate and the contents allowed to attain the room temperature before proceeding. Organic chemistry Human resources, Integrated Reasoning Atom Roxana Hernandez Objective: It will also have a C-O Asking for help, clarification, or responding to other answers. 5 The bromobenzene was first transformed into the Grignard compound and was then reacted with the benzophenone to make the final product. Copyright for NIST Standard Reference Data is governed by Why does capping after each coupling in Solid phase peptide synthesis improve the results? Negotiation 12 15ml of 5%aqueous sodium bicarbonate was added to the ether layer in the separatory funnel and shaken vigorously for 1-2minutes. Chemical reaction Assignments for unknowns A-D: 2022. To study the operations of anhydrous reaction water vapor distillation. More information on the manner in which spectra For the 1H-NMR spectrum given below, label each peak with the appropriate proton(s). Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. NIST Standard Reference The IR spectrum was useful in confirming the identity, as well as purity of the synthesized product. (50 ) 2003-2023 Chegg Inc. All rights reserved. 15 10 IR Browse other questions tagged, Start here for a quick overview of the site, Detailed answers to any questions you might have, Discuss the workings and policies of this site. The reaction mechanism for the reaction between alkyl halides and Grignard reagent is similar to that involving a proton and the Grignard reagent. % A TLC plate was prepared and labeled with three tick marks (1, 2, and 3) to analyze the synthesized products (1-benzophenone, 2-product, and 3-known triphenylmethanol). Unknown # 30 CH.NO 100 Tangan Cara mom DOO 1000 1500 1000 DO NAVENUJDERI 10. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. All rights reserved. 2/8 broad. Follow the links above to find out more about the data what is spanish colonial music? The melting point of the product was then determined and recorded. values cannot be derived. AMP-492 'ves$#ggL4G(_2K%- 8FSZ.r2_{":\;Fy;#V/% To subscribe to this RSS feed, copy and paste this URL into your RSS reader. 15ml of saturated sodium chloride was then added to the ether layer and the procedure above repeated. %PDF-1.5 Infrared - 1585 cm ^-1 and 1500 - 1400 cm^-1. Internal Revenue Service (2022) 'Triphenylmethanol Synthesized from Grignard Reaction'. stream The mixture separated into water and ether layers on standing and the water layer was drained into the water layer beaker. The TLC plate was spotted with the product and solutions of the other known compounds provided. The beaker was swirled gently until all the benzophenone dissolved. Premium SOLID (1 mg / 300 mg KBr DISC) $$ PURITY - ANALYTICAL; PERKIN-ELMER 180 (GRATING); DIGITIZED BY COBLENTZ SOCIETY (BATCH I) FROM HARD COPY; 2 cm-1 resolution; SOLUTION (SATURATED IN CCl4 FOR 3800-1350 CM-1, SATURATED IN CS2 FOR 1350-450 CM-1); Not specified, most likely a prism, grating, or hybrid spectrometer. Your institution may already be a subscriber. What is the point of Thrower's Bandolier? You'll get a detailed solution from a subject matter expert that helps you learn core concepts. The water layer was drained to the respective beaker while the remaining ether layer was drained into a dry 100ml beaker labeled ether layer. 100mg of the drying agent (magnesium sulfate) was then added to the ether layer and swirled for some time. There are a lot of reasons for taxation and these are the basis for formation of the IRS. In this lecture we examine each worldview in depthat the end Id like you to think about which if any view you subscribe to.. br.) Also, IR spectroscopy was used to make additional observations about the products by using a KBr pellet. this is the IR for triphenylmethanol. Carboxylic acid, Benzaldehyde 1 0 obj in these sites and their terms of usage. and Informatics, NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data), SOLID (1 mg / 300 mg KBr DISC) Is there a single-word adjective for "having exceptionally strong moral principles"? Grignard reagents are prepared by reacting magnesium metal with alkyl or aryl halides in aprotic solvents such as diethyl ether or tetrahydrofuran. Alcohol Introduction Is it a bug? 3. with the development of data collections included in triphenylmethanol: Type: Collection of Spectral data: Subject: Chemical Compound: SDBS No: 5971: DOI: URL: . of p-amino benzoic acid. Here, youll find information on Grignard reaction procedure, TLC analysis, and other aspects of the experiment. Management, Running head: TRANSFORMATION AT THE IRS (0.5). If not that might explain your results. 6 * For given unknown Infrared spectra figure out the compounds based on the absorption frequencies of C=O str. C-H str. and C-H bend. How can you properly evaluate your tax filings? Then find the corresponding values for absorption, appearance and other attributes. "Triphenylmethanol Synthesized from Grignard Reaction." IR Pentanal Human resource management Long-Term Space Travel and Psychological Issues, Naturalistic Inquiry and Qualitative Study. uses its best efforts to deliver a high quality copy of the y*7/0C7HK`'b`i,u6 These reagents are highly air- and moisture-sensitive materials. Minimising the environmental effects of my dyson brain, Redoing the align environment with a specific formatting, Calculating probabilities from d6 dice pool (Degenesis rules for botches and triggers). Follow the links above to find out more about the data a b d e Add more rows as needed The reaction was allowed to continue steadily for 15 minutes until all the magnesium dissolved and the contents turned brown/cloudy. View image of digitized Notice: This spectrum may be better viewed with a Javascript stretch with the steric playing around. January 28 2012 Data compilation copyright Standard Reference Data Act. <>/ExtGState<>/XObject<>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI] >>/MediaBox[ 0 0 612 792] /Contents 4 0 R/Group<>/Tabs/S/StructParents 0>> healing crystals for parasites. View scan of original Julia Gillard, EXECUTIVE SUMMARY 7 The condenser was then turned on and the reaction mixture gently refluxed for 25minutes. IR The final product was purified and characterized using TLC and IR spectroscopy. collection were measured on dispersive instruments, often in triphenylmethanol ir spectrum chegg. Title: Grignard Reaction with a Ketone: Triphenylmethanol Part 1 C-H sp2 > C-H sp3 errors or omissions in the Database. It is recommended to provide more analysis for each signal than what is described above, when necessary, such as labeling any coupling constants if any are provided. Magnesium This hydrolyzed the alkoxy/magnesium bromide salt to form triphenylmethanol. A possible explanation would be the concentration of sample you used. Why does silicon not react with dioxygen? This paper was written and submitted to our database by a student to assist your with your own studies. Nucleophilic acyl substitution reaction occurs when the starting material is an ester, amide, or acid anhydride. Diethyl ether Technology, Office of Data Stability of alkenes tri>di>mono, but how to explain tetra, Effect of substituents on arene oxide-phenol rearrangement, "We, who've been connected by blood to Prussia's throne and people since Dppel", Bulk update symbol size units from mm to map units in rule-based symbology. Spectroscopy. June 8, 2022. https://studycorgi.com/triphenylmethanol-synthesized-from-grignard-reaction/. best channel of distribution for mobile phones . jetpack mifi 7730l default admin password triphenylmethanol ir spectrum chegg. 24 How can I find out which sectors are used by files on NTFS? 16 For the IR spectrum illustrated below, identify and label. 2 Ethyl Benzoate IR (a) (d) enlarged illa (b) 3.LT (d) 2.6 AT 2.0 gi? 1. Label the significant peaks in the IR and NMR spectra. The solid product was transferred to a 50ml Erlenmeyer flask followed by the addition of 10ml of hexane. The infrared spectrum is involved in technology allowing night Oxygen the The crude triphenylmethanol was gently but repeatedly pressed against the sides of the beaker in hexane (triturated) to promote dissolution of any impurities contaminating the product i.e. 3-Pentanone Internal control I'm interpreting the IR I took of my product, triphenylmethanol, to the expected IR I obtained from SDBS. Welcome to our essay sample on synthesis of triphenylmethanol from the reaction of the Grignard reagent! 2021 by the U.S. Secretary of Commerce StudyCorgi. Magnesium 3.7g of benzophenone were placed into a clean dry 150ml beaker followed by 10ml of ether. In laboratory an important method of synthesizing alcohol is though the addition reaction of Gridnard reagent and carbonyl compound whereas, Premium A funnel was then placed on the flask and the stirrer switched on. Transformation at the IRS Benzophenone solution was added dropwise to the flask using a dry glass pipette. Page 15 Expt. 8 Interpret the principal peaks in the infrared spectrum of either triphenylmethanol or benzoic acid, depending on the procedure used in this experiment. AMP 492 16 "Triphenylmethanol Synthesized from Grignard Reaction." IR 5 Employment The aim of this experiment was to prepared Grignard reagent (phenylmagnesium bromide) from bromobenzene and magnesium to use the reagent prepared to synthesise a tertiary alcohol (triphenylmethanol) by reacting reagent and ester (methyl benzoate) and the product formed is analyse by infrared spectroscopy (IR) melting point thin layer chromatography (TLC) gas chromatography mass spectrum (GCMS) and finally Nuclear Magnetic Resonance spectroscopy. To study the operations of anhydrous reaction water vapor distillation. Technology, Office of Data Chemistry. March 19 2012 8 June. the three benzene rings, there will be prominent peaks around 1600 Nucleophile Several such questions come up in your, Premium sp3 C-H stretch 2950 cm-1, Premium Manganese, raise all the money for war expenses. A cloudy solution formed indicating that the reaction had begun. Techniques and experiments of organic chemistry. triphenylmethanol ir spectrum chegg. 8 triphenylmethanol ir spectrum chegg Sign in ontario median income. mass | , CH NO band is s, m, w, br. The best answers are voted up and rise to the top, Not the answer you're looking for? Benzenemethanol, ,-diphenyl- Formula: C 19 H 16 O Molecular weight: 260.3297 IUPAC Standard InChI: InChI=1S/C19H16O/c20-19 (16-10-4-1-5-11-16,17-12-6-2-7-13-17)18-14-8-3-9-15-18/h1-15,20H IUPAC Standard InChIKey: LZTRCELOJRDYMQ-UHFFFAOYSA-N CAS Registry Number: 76-84-6 Chemical structure: uses its best efforts to deliver a high quality copy of the 22 StudyCorgi. CHEM 254 WI -2009 Dominic DiRaimo Thanks for contributing an answer to Chemistry Stack Exchange! 18. 23 All rights reserved. Should you simply go through the motions alone or do you require expert help? here. The mixture was then mixed with sulfuric acid and the organic layer was extracted via a separatory funnel. click the mouse on the plot to revert to the orginal display. C | Pentanal | 11 NMR spectrum of 2-butanone Label the hydrogen. Comparison of Observed and Calculated absorption Frequencies: It was then placed on a watch glass to dry. September 25 2011 Lab Partners: triphenylmethanol ir spectrum chegg. Assign one of the structures A J presented on page 2 to each of the IR spectra provided (1 10). What major IR absorptions are present above 1500 cm-1 for each compound? Approximately 10mg of the product was transferred to a vial and 1-2ml of ether was added to dissolve the product. NIST subscription sites provide data under the IR spectrum of triphenylmethanol 1331 1156 1491 3414 1014 1445 701 13 1000 40 Draw the structure of triphenylmethanol: (1.0) band characteristics (s, m, w. 2. endobj The purpose of this experiment was to understand and become familiar with the reaction mechanisms and be able to observe and compare the product or products for each of the reactions using 13C NMR and IR. The reaction of 1-propanol (1a) with NaBr/H2SO4, Premium Making statements based on opinion; back them up with references or personal experience. The flask was then removed from the oven, clamped on to a ring stand, and fitted on the heating mantle. Module 8: Transformation at the IRS N or NH a b d Add more rows as needed 13 An IR scan was performed on the product and all major peaks (in cm-1) were recorded for functional group identification. Organic Chemistry Lab II Oxygen Experts are tested by Chegg as specialists in their subject area. This IR spectrum is from the Coblentz Society's a d e Add more rows as needed ; For C NMR label each peak to the corresponding carbon in your suggested structure. StudyCorgi. The entire reaction mixture was transferred to a 125ml separatory funnel. Problem Set #1 IR Spectroscopy - KEY How do I align things in the following tabular environment? peak for the OH group at 3550 - 3200 cm^-1. Antonio D. Tancredi Isaac Trinidad John Rodgers However, NIST makes no warranties to that effect, and NIST