Chem 460 study guide Exam 1
Chem 460 study guide Exam 1 Chem 460
Edinboro University of Pennsylvania
Popular in Forensic Analysis
Popular in Chemistry
verified elite notetaker
This 16 page Study Guide was uploaded by Katelyn Vogel on Tuesday February 23, 2016. The Study Guide belongs to Chem 460 at Edinboro University of Pennsylvania taught by Dr. Rogers in Spring 2016. Since its upload, it has received 26 views. For similar materials see Forensic Analysis in Chemistry at Edinboro University of Pennsylvania.
Reviews for Chem 460 study guide Exam 1
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 02/23/16
Chem 460: Forensic Analysis Study Guide: Exam 1 Chapter 1 1. Where did forensic chemistry originate? Rome 2. What Latin term does forensic refer to? “forum” 3. What Greek term does science refer to? “knowledge” 4. Forensic chemistry is applied analytical chemistry. TRUE 5. What three components make up forensic chemistry? qualitative analysis, quantitative analysis, and comparison 6. Forensic chemistry is used to answer legal questions. FALSE, forensic questions . 7. What three tasks are accomplished when working with evidence? identificationclassification, andindividualization 8. When classifying evidence, the smaller the class, the more meaningful the evidence. TRUE 9. What tools are used in the scientific method? experimentation & observation 10. What is criminal law? when courts settle disputes between individuals & the state 11. What is civil la? when courts settle disputes among individuals or entities 12. What system guides the law, precedent, & function of the courtsadversarial system 13. What system does science employ? scientific method 14. Which party is known for filing charges in court? plaintiff/prosecution 15. Which is the accused party? defendant 16. What is therier of fac To whom the evidence is presented & who will make the decision 17. What is precedent? knowledge gained previously in similar settings 18. What is different between chemistry & the law? the systems 19. What is the relation between chemistry & the law? precedents 20. What is a grand jury? special type of jury that is empowered to decide if the evidence against the defendant warrants proceeding to the next step 21. What are examples of pattern/experience evidence? fingerprints, firearms examination, toolmarks, bite marks, impressions, bloodstain pattern analysis, handwriting & hair 22. What are examples for analytical evidence? DNA, coatings, chemicals, materials, fluids, serology, fire & explosive analysis 23. Which labs are the best equipped and staffed? Federal labs 24. State and local labs do the most work. TRUE 25. What are the laboratory based disciplines in FS? DNA, drug analysis, toxicology 1 Chem 460: Forensic Analysis Study Guide: Exam 1 26. What are the expert interpretation based disciplines in FS? bite marks, tool marks, firearms, & fingerprints 27. What is the goal of forensic analysis? individualization! 28. How many techniques apply individualization? 1 → DNA 29. What rule sets the standard for thegeneral acceptance of evidence? The Frye Rule 30. What is important about the Daubert decision? in the Supreme Court, the judge decides what is admissible (gatekeeper) 31. This decision applies to state and federal cases. FALSE, only federal cases . 32. What do studies lack in the forensic disciplines? peerreviewed, publication in reputable journals, establishing a scientific basis for the analysis & the validity of the analysis 33. How do these weaknesses affect forensic expert testimony? It hinders the reliability & accuracy of scientific methods 34. What happens when admissibility is an issue? the judge can convene admissibility hearings to determine the merit of the method 35. Where is bias & error important in human observation? fingerprinting & eyewitness testimony 36. What are the two major criteria for a governing body? strongly rooted in science & not be part of a law enforcement agency 37. Which case established the relevancy of evidence? General Electric v. Joiner (1997) 38. What is important about the Kumho decision? the judge’s gatekeeper role was expanded to include all expert testimony 39. What three cases make up the Daubert trio/trilogy? Daubert v. Merrell Dow Pharmaceuticals (1993), General Electric v. Joiner (1997), & Kumho Tire Co., Ltd. v. Carmichael ( 1999) 40. How many areas make up the Forensic Science Standards Board (FSSB)? 24 41. What is the difference between inclusive evidence & exclusive evidence? Inclusive evidence includes a person or possibility Exclusive evidence excludes a person or possibility 42. What is the difference between direct evidence & circumstantial evidence ? Direct evidence known to a person by personal knowledge Circumstantial evidence requires inference to move logically from the information provided to the answer to a question 2 Chem 460: Forensic Analysis Study Guide: Exam 1 43. Give an example of direct evidence: eyewitness testimony 44. What is the chain of custody? a paper trail recording the history and tracking the location of evidence 45. What is destructive testing? when evidence is consumed in testing 46. What are the three groups of techniques relied on by forensic chemists? visual examination and inspection, organic and inorganic chemical analysis 47. What is the sample or exhibit known as in this step? general unknown 48. What presumptive test can be performed for identification in the first step? wet chemical methods 49. What can be used for separation and isolation in the second step? extraction, chromatography, headspace methods, & solidphase extraction 50. What tests can confirm tentative identification? infrared spectrophotometry & GCMS 50. Name 8 qualifications for the forensic mindset. a. assume nothing b. be resourceful c. think outside the discipline d. be creative e. build a big toolbox that never stops growing f. know limitations g. be flexible h. be persistent 51. What are the two areas of analytical chemistry in the forensic field? forensic toxicology & forensic chemistry 52. What is the difference between these two areas? Forensic toxicology biological evidence Forensic chemistry physical evidence 53. Which area is associated with death investigation? forensic toxicology 54. What organization(s)/association(s) relate to forensic chemists? The American Chemical Society (ACS) The American Board of Criminalistics (ABC) American Society of Crime Laboratory Directors LAB program (ASCLD) 3 Chem 460: Forensic Analysis Study Guide: Exam 1 Chapter 2 1. What is metrology? the science of measurement 2. What two criteria judge the data produced in forensic co utility & reliability 3. What is USAP? NumberUnitsSpreadAssessmentPedigree it contains qualitative & quantitative criteria associated with a numerical result 4. What is themeasurand ? the quantity being measured or determined 5. What is a pedigree? history or precedent used to gather the data/shows reliability of the data 6. What are some examples of elements of a pedigree? traceability of weights & standards, lab protocols & methods, analyst training, lab accreditation, & analyst certification 7. What is ncertainty? range that characterizes the expected spread or dispersion of a measured result 8. Having uncertainty gives the data have less credibility. Fgreater . 9. What is error? difference between an individual measured result & the true value 10. Which type of “zeros” anot considered for significant figures? leading 11. Which type of “zeros” are considered significant? embedded 12. What is the rule about “trailing zeros”? only significant when there is a decimal place 13. When should you round an answer? at the end of the calculations 14. What isabsolute uncertaint? certain value given on measured devices 15. What iselative uncertain percentage uncertainty 16. What formula is used to combine relative uncertainty values? 17. What does this equation represepropagation of uncertainty 18. What is a replicate measurement? measurement of a criterion or value under the same experimental conditions for the same sample used for the previous measurement 19. What is another name for the normal distribution? Gaussian distribution 20. What is the average defined as? the population mean, μ 21. What is the subset of a population defined as? the n ple, 22. What is the twopart goal of any sample? to ensure thn is sufficiently large to appropriately represent characteristics of the parent population and to assign quantitative, realistic, & reliable estimates of the uncertainty that is inevitable when only a portion of the parent population is studied 4 Chem 460: Forensic Analysis Study Guide: Exam 1 23. What is the sample mean? the sum of the individual measurements, divided bn 24. The context dictates the rounding procedures. TRUE 25. What is bsolute error? the difference between the true value & the experimentally obtained value with the sign retained to indicate how the results differ 26. How is % error calculated? % error = [(experimental value true value)/true value] x 100 27. When it is commonly used? to express the accuracy of an analysis when the true value is known 28. What is the limitation of % error? does not take into account the spread or range of the data 29. What is thestandard deviation? average deviation from the mean & measures the spread of the data 30. What does a small SD represent? the replicate measurements are close to each other the distribution is narrow the closer the grouping & the smaller the spread 31. What does it mean to have a large SD? the replicate measurements are spread out over a larger range of values the distribution is relatively wide 32. What two values are reported for SD?opulation σ) & sample (s) 33. What percentage is represented by ± 1 SD? 68% 34. What percentage is represented by ± 2 SD? 95% 35. What percentage is represented by ± 3 SD? 99.5% 2 36. What is the samplevariance (v)? s 37. Which is favored by forensic chemists? standard deviation 38. How is the significance of a SD expressed? by the percent relative SD ( %RSD) 39. What are other names for the %RSD? coefficient of variation (CV) or the percent CV 40. How is the %RSD calculated? %RSD = (SD/mean) x 100 41. How many decimal places is the %RSD reported to? 2 42. Why? It is used comparatively & the value is not the basis of any further calculation 43. What is one way to account for a small number of samples? apply a multiplier called the Studentvalues confidence interval (CI) = st√/ n 5 Chem 460: Forensic Analysis Study Guide: Exam 1 44. How is that result reported? as a range about the mean: x √ st / n 45. The percentage is a measure of quality. FALSE, certainty . 46. What isaccuracy? the closeness of a test result or empirically derived value to an accepted reference value 47. What isbia (total systematic error)? the difference between the expected and experimental result 48. What isprecision the reproducibility of a series of replicate measurements obtained under comparable analytical conditions 49. What israndom error? Errors that are not the same, not reproducible, equally +/, & generally small 50. What isystematic error? analytical errors that are the same every time & that are not random 51. What are the two goals of method development, validation, & implementation? minimization of errors & development of a defensible uncertainty 52. What is the two categories of error? those originating from the analyst & those originating with the method 53. What is the purpose of method validation? to minimize & characterize method error 54. What are systematic errors? predictable & impart a bias to the reported results 55. What are large random errors typically called? Gross errors 56. What is the goal ohypothesis testing? to answer a specific question using calculations and statistical distributions 57. What is another name for hypothesis testinsignificance testing 58. What are outliers? 59. What test is used for outliers in analytical chemistry?Dixon test 60. What does the Dixon test say? Q = |gap/range| calc 61. What is the gap? the difference between that point & the next closest point in ascending order 62. What is the range? the spread from low to high in ascending order 63. What is another test used for outlieGrubbs test 64. What does the Grubbs test say? G = |questioned mean|/s 65. If one test says to discard a value & another says to keep it, the value is discarded. FALSE, kept . 6 Chem 460: Forensic Analysis Study Guide: Exam 1 66. What is the goal of ttest for two data sets? to determine whether the spread of the two sets of data overlap sufficiently for one to conclude that they are or are not representative of the same population 67. What isType I error? an error in which the null hypothesis is incorrectly rejected 68. What isType II error? an error in which the null hypothesis is incorrectly accepted Chapter 3 1. What is Quality assurance (QA)? allencompassing, “cradletograve” system that controls data generation 2. What is Quality control (QC)? procedures, policies, & practices designed to assure data quality 3. What is total quality management ? the practices & procedures used within an organization such as a forensic lab 4. What are the two important aspects of QA/QC? accreditation and certification 5. What is the difference between them? analysts are certified & laboratories are accredited 6. What is the most common certification body? AAFS 7. What is accreditation? multistep process that examines everything from the physical plant of a lab through its analysts & management structure 8. If the data are quantitative, the uncertainty of the results should be estimated. TRUE 9. What is fitness for purpose? insuring the utility of the data produced 10. What is the purpose of the chain of custody documentation? to provide an unassailable record of the history of an exhibit of evidence from its creation or collection through its final deposition be it destruction or storage 11. Why is it important for each analyst to make separate cuts to gain access to the evidence? it insures that anyone who handled the exhibit can look at it while testifying in court and immediately not whether his/her seal remains intact 12. What is the most important pieces of lab documentatiostandard operating procedure (SOP) 13. What is an SOP? a detailed description of how a procedure is to be executed 14. What are some advantages to the concept of standardization? ensure “data comparability,” optimization, & validation 15. What is the NIST? National Institute of Standards & Technology 7 Chem 460: Forensic Analysis Study Guide: Exam 1 16. What is the role of NIST? to promote the standardization of weights & measures to serve the needs of industry, commerce, science, & technology. Forensically, to create, maintain, & supply standard reference materials (SRMs) 17. What is a NIST Certified Value? value & its uncertainty assigned by NIST in conformance with the NIST uncertainty policy 18. What is traceability data can be linked, related, or traced to an unassailable original source 19. Traceability is the central premise of QA. TRUE 20. What is traceability an example of? chain of custody 21. Traceability is a foundation of method validation. TRUE 22. What is method validation? process in which its fitness for purpose is verified & the operational parameters & limitations are developed, defined, & documented 23. What is a key component of total quality management in a lab? method validation 24. What is a validated method? to fit for purpose & produce the best possible data for a given analyte or group of analytes such that the data are acceptably accurate, precise, quantifiable, timely, & reliable 24. What is figures of merit? the operational parameters of a method 25. List & define the figures of merit. a. accuracy closeness of agreement between a measure quantity & a true quantity of a measurand i. combination of trueness & precision b. bias difference between an experimentally determined value & an accepted reference value c. limit of detection (LOD) the lowest concentration of an analyte that can be unambiguously detected, but not necessarily quantitated d. limit of quantitation (LOQ) the lowest concentration of an analyte that can be determined with acceptable precision (repeatability) & accuracy for a given method e. precision closeness of agreement between indications or measured quantity values obtained by replicate measurements on the same or similar objects under specified conditions i. expressed as standard deviation or %RSD 8 Chem 460: Forensic Analysis Study Guide: Exam 1 f. repeatability closeness of the agreement between the results of successive measurements of the same measurand carried out subject to all the following conditions: i. the same measurement procedure ii. the same observer iii. the same measuring instrument used under the same conditions iv. the same location v. repetition over a short period of time g. reproducibility closeness of the agreement between the results of measurements of the same measurand, where the measurements are carried out under changed conditions such as: i. principle or method of measurement ii. observer iii. measuring instrument iv. location v. conditions of use vi. time h. robustness a measure of a method’s capacity to remain unaffected by small but deliberate variations in method parameters i. ruggedness the degree of reproducibility of test results obtained by the analysis of the same samples under a variety of conditions such as different labs, analysts, instruments, lots of reagents, elapsed assay times, assay temperatures, or days j. sensitivity quotient of the change in an indication of a measuring system & the corresponding change in value of a quantity being measured k. trueness closeness of agreement between the expectation of a test result or a measurement result & a true value i. expressed in terms of bias ii. systematic component of accuracy l. uncertainty parameter associated with a measurement result that characterizes the dispersion (spread) of the values that could reasonably be attributed to the particular quantity being measured. 26. What are the steps to validating a method? direct questions toward fitness for purpose, develop a method validation plan, lab work 27. What is a batch? a group of samples & related QC samples 9 Chem 460: Forensic Analysis Study Guide: Exam 1 28. What constitutes a batch? the type of sample being analyzed 29. What controls should a batch contain?positive contro & negative control orblank 30. The number of control samples required per batch increases proportionately. TRUE 31. What are blank samples? used to make sure that glassware, equipment, & instrumentation are free of the analyte of interest & potential interferences 32. What do blanks provide? information about the accuracy of the technique used 33. What are open controls orknowns? practice samples for the analyst that have known reliable values 34. What does a known provide? measure of expected bias; detection & diagnosis of systematic errors 35. What are blinds or blind control? samples in which the true value may be known to someone within the lab or to someone outside or above the lab hierarchy, but not to the analyst 36. What are calibration checks? usingcalibration curves, analyses are performed on calibrated instruments 37. What are replicate? subsamples 38. What does at least 3 replicates allow for? calculation of simple statistics s, %RSD) 39. What are duplicates? separate sample from a separate source 40. What are spikes? compounds purposely added at known levels & used to gauge the recovery of an analyte from a specific matrix & sample 41. What challenge do spikes present? finding components chemically similar to the target analytes that are unlikely to be found in the sample 42. What is the process of calibration? linking an instrumental response or readout to performance 43. What does calibration & calibration checks ensure? that the device’s output is reliable 44. What is one of many routinely calibrated equipment? analytical balances 45. If equipment provides measurement data, it does not need to be calibrated. FALSE, it must . 46. What are control charts running record of the performance of a device or solution that identifies when performance is no longer within accepted uncertainty ranges 47. What are the lines represent on a control chart? warning limits & action limits 10 Chem 460: Forensic Analysis Study Guide: Exam 1 48. What is aregression line? a line describing the points that have a linear relationship or correlation, y = mx + b 49. What must be taken into account for the validity of a calibration curve? passage of time 50. What is thedependent variable? y 51. What is th independent variable? x 52. What is th linear range? the range in which the relation between concentration & response is linear 53. What is thelinear dynamic range (LDR)? a figure of merit that is linear from 1 ppb to 1 ppm on a calibration curve 54. What is thelimit of quantitation (LOQ) the concentration corresponding to the lowest concentration in the linear range 55. What is thelimit of detection (LOD)? the concentration at which no significant response can be detected 56. What is aleastsquares regression/leastsquares f? a fit of a line or other curve to a set of points that is optimized by minimizing the total distance of all points to the curve; to eliminate potential canceling of + & 57. What is ainear regression? the process of creating a straight line & linear equation to describe the relationship between a dependent & independent variable 2 58. What is thecorrelation coefficien R 59. How is the ideal calibration check (CC) obtained? from an accepted reference standard that is independent of the solutions used to prepare the calibration standards 60. Why is CC important? it is the only method that facilitates the detection of a problem in the stock solution 61. What four factors contribute to the validation of a calibration curve? a. correlation coefficient, b. the absence of a response to a blank c. the time elapsed since the initial calibration or update d. performance on an independent calibration check sample 62. What is a calibration check sample? a sample prepared independently of the calibration curve & used to detect problems with the curve 11 Chem 460: Forensic Analysis Study Guide: Exam 1 63. What are the types of curves? a. external standard a calibration curve in which the standards are made in simple solvents that may not match the matrix i. works well when matrix effects are minimal b. internal standard a calibration method that involves the addition of internal samples to all samples & standards & to which concentration & responses are ratioed i. must mimic the chemical behavior of the analyte ii. cannot be compound that might occur in the sample 64. What is matrix mismatch? the situation that arises when the solvent system used to generate a calibration curve does not match the matrix of the sample 65. What is the principle of the internal standard calibration? ratios of the concentrations & responses are used, rather than uncorrected concentration & responses 65. What is a type of internal standard curve ? standard addition 66. What is standard addition ? a calibration method which uses the samples as the matrix & to which increasing aliquots of the target analyte are added 67. What are the two disadvantages to standard addition? large amount of sample consume & the difficulty in adapting the approach to routine analysis Chapter 5 1. What must exist for partitioning to occur? a phase boundary 2. Why does partitioning occur? the analyte has a greater affinity for one phase over the other, owing to charges, polarity, & other chemical properties 3. What principle is invoked to drive the equilibrium to one side or the other? Le Chatelier's principle 4. The more complete the process, the efficient the separation. TRUE 5. How are samples prepared for inorganic analysis? use of acid digestions 6. What are digestions? isolation of the elemental components but destroy the organic & biological components present in the matrix 12 Chem 460: Forensic Analysis Study Guide: Exam 1 7. What do organic extractions do? pluck the analytes from the matrix 8. What is the goal of quantitative analysis? to isolate the analyte from the matrix & to transfer the analyte quantitatively to the final analytical solution 9. What is the difference between extraction and digestion? extraction is the removal of analyte by organic analytes & digestion is the destruction of the matrix to reach the analyte by inorganic analytes 10. What two conditions must be met to extract an analyte from a matrix? a. there must be an exploitable difference in a chemical or physical property between the matrix & the analyte b. there must be an equilibrium condition that can be manipulated 11. What does Henry’s law state? the partial pressure of the analyte above a liquid is proportional to its concentration in the liquid 12. What is this law the basis for? presumptive breath alcohol tests 13. What is the equilibrium constant f or Henry’s law? KH 14. What is the reason for most organic sample preparations? the manipulation of equilibrium conditions 15. Separation must be 100% complete. FALSE, as long as enough of the analyte is separated & the separation is reproducible, it can be used qualitatively & quantitatively 16. What is the generic expression of equilibrium? aA + bB → cC + dD 17. What is favored when K < 1? reactants 18. What is favored when K > 1? products 19. How do you increase the solubility of a drug? convert the drug to a soluble salt 20. What are some common drug salts? sodium, calcium, sulfates, chlorides, tartrates, citrates, & lactates 21. How are soluble compounds characterized? hydrophilic or lipophobic 22. What is K ? solubility product sp 23. What is Kspreferred to as in nonequilibrium conditions? Q 24. What does it mean when Q > K spa solid forms 25. What else plays a role in solubility & precipitation reactions? thcommon ion effect 26. What is it? the effect of ions present but not part of the reaction of interest 27. What is lipophilicity? “fat loving” molecules that are more soluble in fats & oils than in water 13 Chem 460: Forensic Analysis Study Guide: Exam 1 28. What is KOWhe octanolwater partition coefficient 29. When is a partition coefficient established? between two phases & an analyte that does not undergo an chemical changes when moving between one phase & the other 30. What is the generic form of the equilibrium constant for partitioning? K D 31. What does the value KDdepend on? relative affinity 32. What are the possible basis for affinity? a. volatility b. polarity (like dissolves like) c. hydrogenbond interactions d. ionion interactions e. iondipole interactions f. dipoledipole interactions 33. What functionalities in drugs define their class? amino groups, phenolic groups, & carboxyl groups 34. Which groups are acids? phenolic & carboxyl 35. Which groups are bases? amino 36. Are these strong or weak acids/bases? weak 37. What is an onizable center? an acid or base group 38. What is a drug soluble in when it is ionized? water 39. What is a drug soluble in when it is unionized? solvents 40. Acidbase characteristics are directly related to solubility. TRUE 41. What is theHendersonHasselbalch equation? the relationship between pH & pKafor large molecules with a single weakacid site 42. What are monobasic acids ? large molecules with a single basic site 43. What is needed to determine if a drug is an acid or base? a. the drug’s K value a b. knowledge of the structure & functional groups c. ionization centers 44. What must the concentration of protons be for it favor protonation? high 45. What is adry extraction? a simple onestep extraction method in which a solvent is added to a solid sample 14 Chem 460: Forensic Analysis Study Guide: Exam 1 46. What is a liquidliquid extraction (LLE)? when an analyte is separated from one liquid & transferred into another by partitioning 47. What practical considerations are involved in selecting a solvent? a. safety & exposure concerns b. the cost of disposal c. miscibility 48. What two comparisons can be made for an analyst to select candidate solvents for a separation LLE? miscibility & polarity 49. Which extraction is best for qualitative data? LLE 50. Which extraction is best for quantitative data? solid phase extraction 51. What is the solvent of choice for solubility of neutral molecules? organic solvents 52. What is the basis for this? polarity & according to like dissolves like 53. What is the solvent of choice for the solubility of salts? water 54. What is the basis for this? spalues 55. Once dissolved, what is the solubility dependent on? pH 56. When is a drug best absorbed through lipid membranes? when it in its most unionized form 57. What is exploited in LLE & in solidphase extractions (SPEs) to maximize separation? pH of an aqueous phase 58. What does it mean for a drug to be amphoteric? has more than one ionization center 59. What challenge do they present? extraction & partitioning 60. Why? the two ionization centers work against each other 61. What does it mean to have a larger Kastronger acid 62. What does it mean to have a larger pKa weaker acid 63. Smaller pKa lues will dissociate first. TRUE 64. How do you determine the ideal pH for extraction? calculate the isoelectric point/isoelectric pH 65. What is the isoelectric point? the pH at which a molecule with multiple ionization centers is neutral 66. What is the diion referred to aszwitterion 67. What two solubilities have to be considered for drugs with ionizable centers? intrinsic solubility & 68. What is intrinsic solubility (0? the solubility (in water) of the unionized form of a drug 69. What is the pH value? max the max pHdependent solubility of that particular drug & salt formation 15 Chem 460: Forensic Analysis Study Guide: Exam 1 70. What determines whether a drug is acid or basic? its structure 71. Ionization percentage are comparable but pH values are not. TRUE 72. What is solid phase partitioning? the analytes to be separated are dissolved in a solvent that moves through a column past a stationary phase on which interactions occur 73. What is the stationary phase? a solid immobile material to which an active material is bound 74. What is the mobile phase ? the phase that moves over the solid or stationary phase 75. What are some of the stationary phase exploitable interacts? adsorption, solubility, binding, & electrostatic interactions 76. What is solid phase extraction (SPE)? 77. What can SPE be classified by? the relative polarity of the solid & mobile phase 78. What is the reversed phase ? a nonpolar solid phase that preferentially associates with nonpolar or slightly polar analytes 79. What is an advantage of SPE over solvent or LLE methods? multiple solvents can be used to clean the sample before the final eluting solvent is added 80. What is solid phase microextraction (SPME)? extraction into a solid phase coated on a microfiber 81. What type of crimes is this typically used for? Arson 82. What is hinlayer chromatography (TLC)? chromatography in which the solid phase is coated on a support such as glass & solvent is drawn up by capillary action 83. What is the most widely used solid phase? silica gel 84. What is the interaction? adsorption 85. What is a retention factor? the distance that a compound migrates relative to the starting point in TLC 16
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'