October 2021 Chemical Technicians Past Paper PDF

COMPILED PAST BOARD EXAM QUESTIONS Licensure Examination for Chemical Technicians October 29, 2021 1. Benzene and its derivatives undergo substitution reactions instead of addition reactions because a. the integrity of...

COMPILED PAST BOARD EXAM QUESTIONS Licensure Examination for Chemical Technicians October 29, 2021 1. Benzene and its derivatives undergo substitution reactions instead of addition reactions because a. the integrity of the benzene ring and the stable pi-bonding pattern remains intact b. the hydrogens of benzene are relatively loosely bound c. the benzene ring is sterically crowded hence only substitution can occur d. the benzene ring is electron rich 2. Electrophiles are a. electron deficient species b. electron rich species c. electrically neutral species d. positively charged ion 3. SN2 means a. two step nucleophilic substitution mechanism involving both alkyl halide and nucleophile b. one step nucleophilic substitution mechanism involving both alkyl halide and nucleophile c. two step nucleophilic substitution mechanism involving only the alkyl halide d. one step nucleophilic substitution mechanism involving only the nucleophile 4. In the decomposition and dissolution of solids during sample preparation, which of the following is expensive and often the last resort? a. Acid treatment using oxidation b. Fusion technique c. dissolution using ultrasound & appropriate solvent d. Simple dissolution 5. It is important to discard containers that are scratched or abraded on their interior surfaces. The internal surface area of a container, whether used for sample preparation or storage, may cause loss of a. matrix b. analyte c. weight d. ash 6. Glass container is not suitable for a. inorganic trace analyses b. oil and grease determination c. microbiological analyses d. all of the above 7. Which of the following is a primary standard for use in standardizing bases? a. Ammonium hydroxide b. Sulfuric acid c. Acetic acid COMPILED BY: ENGR. IVAN JAN P. ROMERO | [email protected]  d. Potassium hydrogen phthalate 8. A solution has been prepared by transferring 60 mL from Ortho-phosphoric acid 85 % (v/v) H3PO4 and diluting it to 1.0 L, what is the concentration of the new solution. a. 10.10% b. 9.25% c. 12.2% d. 5.10% 9. A student has got three stock standard solutions of 3 different elements, zinc (Zn) 2000 ppm, cadmium (Cd) 1500 ppm and lead (Pb) 1000 ppm. A student took 10 mL from each solution and transfers it to 200 mL volumetric flask then completed to total volume with solvent. What is the final concentration of each element in the diluted mix solution? a. 50 ppm Zinc, 32 ppm Cd, 25 ppm Pb b. 100 ppm Zinc, 75 ppm Cd, 50 ppm Pb c. 75 ppm Zinc, 75 ppm Cd, 50 ppm Pb d. 100 ppm Zinc, 25 ppm Cd, 25 ppm Pb 10. The HPLC column type in which molecules are separated according to size. a. Ion exchange b. size exclusion c. normal phase d. reverse phase 11. During ignition for ashing, muffle furnaces that go up to 1100oC are used primarily for this and ________ is needed to contain the sample. a. porcelain crucible b. evaporating dish c. beaker d. all of the above 12. A graphical representation of measuring signal as a function of quantity of analyte. a. Calibration curve b. Quality Control Chart c. Absorbance Chart d. None of the above 13. In AAS method, If the sample concentration is too high to permit accurate analysis in linearity response range, there are alternatives that may help bring the absorbance into the optimum working range. a. sample dilution b. using an alternative wavelength having a lower absorptivity c. reducing the path length by rotating the burner hand d. All of the above 14. A student has to measure out 9.40 mL of a liquid and selects a 100 mL graduated cylinder. To improve the accuracy of the measurement, it would be most effective to: a. take the average of multiple measurements using the graduated cylinder. COMPILED BY: ENGR. IVAN JAN P. ROMERO | [email protected]  b. measure the liquid using a 25 mL graduated cylinder instead. c. estimate the measurement obtained from the graduated cylinder to an additional significant figure. d. measure the liquid using a 10 mL graduated pipette instead. 15. A buffer solution may be a mixture of a. a weak acid and its salt b. a weak base and its salt c. an excess of a weak acid with a strong base d. all of the above 16. Which statement is true? a. The value of the equilibrium constant increases with the addition of a catalyst b. A catalyst speeds up both the forward and reverse reaction rates c. The greater the activation energy, the faster the rate of reaction. d. A catalyst increases the rate of reaction by decreasing the number of collisions 17. What volume is occupied by 4.00 g of carbon dioxide, CO2 (44.0) gas at a pressure of 0.976 atm and a temperature of 25.00C? a. 0.191 L b. 19.1 L c. 2.28 L d. 22.8 L 18. Molecular oxygen is highly soluble in the blood because a. the hemoglobin molecule can bind up to four oxygen molecules b. the solubility of oxygen is increased by the higher temperature of the body c. pressure is increased inside the body d. pressure inside the body is different outside of it 19. When water is heated in a beaker, bubbles of air form on the side of the glass before the water boils. This shows that a. the solubility of gases in water decreases with increasing temperature b. the solubility of gases in water increases with increasing temperature c. the solubility of gases in water decreases with decreasing temperature d. the solubility of gases in water increases with decreasing temperature 20. The absorbance of different concentrations of potassium permanganate determined through UV- Vis Spectrophotometer is shown below. Concentration, ppm Average Absorbance 1.11 0.015 22.2 0.236 44.4 0.512 66.6 0.751 88.8 1.062 COMPILED BY: ENGR. IVAN JAN P. ROMERO | [email protected] Note: During the actual boards, this table was not given. The Quality Control Sample for this run gave an average absorbance reading of 0.486. The theoretical concentration of the QC sample is 44.4 ppm. Calculate for the error of this QC run. a. 0.0524 b. 0.0552 c. 0.0465 d. 0.00052 21. Method of passing the sample through a metal or plastic mesh of a uniform cross-sectional area to separate particles into uniform sizes. a. sieving b. pulverizing c. macerating d. milling 22. In handling acid wastes, what type of protective gloves should be used? a. Cloth gloves b. Surgical gloves c. Rubber gloves d. Disposal plastic gloves 23. What type of container must be used for acid or alkali wastes? a. Polyethylene Drums b. Metal drums c. Fiber Drums d. Cloth container 24. A solid waste management practice which refers to the controlled decomposition of organic matter by microorganisms, mainly bacteria and fungi, into a humus-like product. a. Composting b. Recycling c. Bioremediation d. Reducing 25. A series of reference standards solutions that have known and accurate pH values at different temperatures used for pH meter calibration. a. Buffer Solutions b. QC Solutions c. pH solutions d. None of the above. 26. Law that states the linear relationship between absorbance and concentration of an absorbing species a. Beer-Lambert’s Law b. Charles Law c. Boyles Law d. Avogadro’s Law COMPILED BY: ENGR. IVAN JAN P. ROMERO | [email protected] 27. Type of quality-control sample used to evaluate the effects of sample matrices on the performance of an analytical method a. Matrix Duplicate b. Matrix Spike c. Method Blank d. Reagent Blank 28. Component of error which, in the course of a number of analyses of the same measurand, remains constant or varies in a predictable way. a. Random Error b. Analyst’s Error c. Systematic Error d. Uncertainty 29. Determine the actual volume contained in a 50.0 mL volumetric flask given the following data: Mass of water: 50.1227 g Density of water at 25˚ C : 0.99707 g/mL a. 50.45 mL b. 50.27 mL c. 50.37 mL d. 50.17 mL 30. It is a pure dry solid substance of known chemical composition used in the direct standardization of solution. a. primary standard b. secondary standard c. analytical standard d. indicator 31. It is the closeness of the agreement between the result of a measured value and a true value. a. Accuracy b. Precision c. Mean d. Error 32. Sample preparation technique used prior to instrumental analysis of metals. a. acid digestion b. liquid-liquid extraction c. sieving d. clean-up 33. Which of the following chemicals may be used to neutralize waste containing caustic soda? a. Potassium Hydroxide b. Ammonia c. Hydrochloric Acid d. Buffer 10 Solution COMPILED BY: ENGR. IVAN JAN P. ROMERO | [email protected] 34. Which of the following are possible routes of exposure of the hazardous effect of waste? a. Inhalation b. Dermal c. Ingestion d. all of the above 35. According to Revised DAO 04-36, the appropriate waste labels shall include: a. Volume of Waste b. Generator ID Number c. Container Material d. All of the above 36. What type of GHS hazard symbol is shown below? a. Corrosive b. Flammable c. Oxidizer d. Explosive 37. Sampling type that eliminates questions of bias in selection a. composite b. stratified c. systematic d. random 38. Reliability of the results decreases with a decrease in the level or concentration of the: a. matrix b. analyte c. reactant d. product 39. Properties of nitric acid making it the preferred acid for digesting samples for the analysis of metals. a. acts as a strong acid b. as an oxidizing agent c. does not form insoluble compounds with metals/nonmetals d. All of the above 40. Possible sources of contamination during sample preparation include: a. Reagents (tracers) b. Glassware/equipment c. Cross-contamination between high- and low-activity samples COMPILED BY: ENGR. IVAN JAN P. ROMERO | [email protected]  d. All of the above 41. The size of the sample taken for analysis depends on the concentration of the a. analyte b. equipment to be used c. specific tests d. All of the above 42. Locating the adulterated portion of the lot for sampling is an example of a. random sampling b. selective sampling c. composite sampling d. stratified sampling 43. Quantitative chemical analysis of weighing a sample, usually of a separated and dried precipitate. a. Titrimetric analysis b. Volumetric analysis c. Gravimetric analysis d. Elemental analysis 44. The substance which does the dissolving and must be greater than 50% of the solution. a. solvent b. solute c. mixture d. solution 45. Requirements of a primary standard. a. High Purity, 99.9% or better b. Stability in air c. Absence of hydrate water d. All of the above 46. Used for vacuum filtration using filter paper. a. gooch crucible b. Buchner funnel c. rotary evaporator d. rubber aspirator 47. In chromatography, ________ is carried out on glass plates or strips of plastic or metal coated on one side with a thin layer of adsorbent. a. HPLC b. GC c. Paper Chromatography d. Thin Layer Chromatography 48. Chromatography is used to a. Separate two or more compounds based on their polarities. b. Separate two or more compounds based on their masses. c. Separate two or more compounds based on how strongly they interact with other d. compounds. e. all of the above COMPILED BY: ENGR. IVAN JAN P. ROMERO | [email protected] 49. A technique for separating mixtures into their components in order to analyze, identify, purify, and/or quantify the mixture or components. a. Spectroscopy b. Chromatography c. Gravimetry d. Titrimetry 50. A graph showing the detectors response as a function of elution time : band’s shapes, position, resolution a. monitor display b. quality control chart c. calibration curve d. chromatogram 51. Under the Bronsted concept of acids and bases, a base is a. a proton donor b. a proton acceptor c. a hydroxide donor d. an electron pair donor 52. Which of the following is NOT an acid-base conjugate pair? a. HCN and CN− b. H2O and OH− c. H2S and OH− d. NH3 and NH4+ 53. Predict the products of the following acid-base reaction: NH3(aq) + HNO3(aq) → a. NH2OH(aq) + HNO2(aq) b. NH4NO3(aq) c. NH4OH(aq) d. no reaction takes place 54. Which of the following is not a common method used for purification? a. Sublimation b. Crystallisation c. Electrolysis d. Chromatography 55. The solution of impure compound and solvent is concentrated to get ____________ a. Unsaturated solution b. Undersaturated solution c. Saturated solution d. Oversaturated solution 56. Insoluble impurities from solution during crystallization are removed by ____________ a. Drying b. Filtration c. Heating d. Cooling 57. Crystal phases can be interconverted by varying ____________ a. Temperature COMPILED BY: ENGR. IVAN JAN P. ROMERO | [email protected]  b. Pressure c. Size d. Viscosity 58. Which of the following is not separated through distillation process? a. Acetone and water b. Aniline and chloroform c. Impurities in seawater d. Milk and water 59. Column chromatography is based on the principle of _______________ (this question appeared twice) a. Ion-exchange b. Exclusion principle c. Differential adsorption d. Absorption 60. Select the correct statement from the following options. a. The lesser the polarity of solute, more strongly it will be adsorbed on a polar surface b. The greater the polarity of solute, more weakly it will be adsorbed on a polar surface c. The greater the polarity of solute, more strongly it will be adsorbed on a polar surface d. All of the mentioned option 61. The elution power of a solvent is determined by ____________ a. Its overall polarity b. The polarity of the stationary phase c. The nature of the sample components d. All of the mentioned 62. The principle on which thin layer chromatography is based is that the ____________ a. Different compounds are absorbed on an absorbent to different degrees b. Different compounds are absorbed on an absorbent to same degrees c. Different compounds are adsorbed on an adsorbent to different degrees d. Different compounds are absorbed on an absorbent to same degrees 63. Which type of chromatography is used for the structural analysis? a. Column chromatography b. Paper chromatography c. Partition chromatography d. Affinity chromatography 64. Affinity chromatography is used for the analysis and isolation of ____________ a. Insoluble starch substances b. Enzyme tyrosinase c. Antibodies bound with a covalently-attached antigen on cellulose column d. All of the mentioned 65. Which of the following is not an application of high performance liquid chromatography? a. Analysis of proteins, drugs and explosives b. Separation of pharmaceutical drugs COMPILED BY: ENGR. IVAN JAN P. ROMERO | [email protected]  c. Elimination of undesirable substances from blood d. Separation of lipids, fatty acids and steroids 66. Which of the following is the application of ion exchange chromatography? a. The softening of hard water b. The demineralisation of water c. The separation and determination of anions d. All of the mentioned 67. The quantitative analysis is done using ____________ a. Ion exchange chromatography b. Thin layer chromatography c. Gas chromatography d. Liquid chromatography 68. The temperature at which solid and liquid coexist in equilibrium is called ____________ a. Melting point of liquid b. Freezing point of liquid c. Freezing point of solid d. All of the mentioned 69. The analysis of electromagnetic radiation scattered, absorbed or emitted by the molecule is called __________ a. Kaleidoscopy b. Astronomy c. Spectroscopy d. Anatomy 70. The different types of energies associated with a molecule are __________ a. Electronic energy b. Vibrational energy c. Rotational energy d. All of the mentioned 71. Select the correct statement from the following option. a. Spectroscopic methods require less time and more amount of sample than classical methods b. Spectroscopic methods require more time and more amount of sample than classical methods c. Spectroscopic methods require less time and less amount of sample than classical methods d. Spectroscopic methods require more time and less amount of sample than classical methods 72. Which of the following is not in the infrared spectrum? a. HCl b. H2O c. CO2 d. CH4 73. The components of the mixture in column chromatography are eluted in order of a. increasing polarity and increasing distribution ratio. b. increasing polarity and decreasing distribution ratio. c. decreasing polarity and increasing distribution ratio. d. decreasing polarity and decreasing distribution ratio. COMPILED BY: ENGR. IVAN JAN P. ROMERO | [email protected] 74. Which equipment must be used in the detection of Pb2+ in blood? a. AAS b. NMR Spectrometer c. IR Spectrometer d. Mass Spectrometer 75. An industrial source of alcohol. a. Coal b. Fats c. Sugar d. Ether 76. What is the most common isotope of hydrogen? a. H has only one isotope b. Protium c. Deuterium d. Tritium 77. A 22/24 stopper is used in a volumetric flask. Which of the following is true? (Same concept as this). a. The diameter is 24 cm and the height is 22 cm. b. The diameter is 22 cm and the height is 24 cm. c. The diameter is 24 mm and the height is 22 mm. d. The diameter is 22 mm and the height is 24 mm. 78. This type of glass is commonly used for laboratory glassware. a. Amber b. Quartz c. Fused silica d. Borosilicate 79. What is the purpose of the apparatus shown below? a. Titrating b. Refluxing c. Filtering d. Distilling 80. In the analysis of a mixture by gas chromatography, which of the following gives the best clue as to whether the components can be analysed with any degree of accuracy? (Same concept) a. Column length b. Retention times COMPILED BY: ENGR. IVAN JAN P. ROMERO | [email protected]  c. Column temperature d. Flow rate of the carrier gas 81. The determination of the equilibrium constant of a colored species can be done via which technique? a. Conductance b. Ion-exchange c. Electrophoresis d. Spectrophotometry 82. Why is there a need to separate halogenated waste from non-halogenated waste? a. Halogenated waste disposal is more costly. b. Non-halogenated wastes are more toxic. c. They are not compatible. d. They will react. 83. Organic peroxides are dangerous when a. Heated b. Concentrated c. Let ether, p-dioxane, THF, among others to vaporize d. All of the above 84. Which of the following can be disposed down the drain? a. 1 g/L PCl5 b. 1 M H2SO4 c. 200 g/L PCl5 d. None of the above 85. This quality system standard is a general requirement for the competence of testing and calibration laboratories. a. GLP b. GMP c. ISO 9000 d. ISO/IEC 17025:2005 86. As P increase while T drops, intermolecular forces are evident, what is applicable? a. Ideal gas is still in effect b. Ideal gas must be replaced by van der waals (???) c. --- d. No change 87. In an ideal gas of volume V and temp T. What happens to T when volume is doubled under constant P? a. Increases b. Halved c. Remains the same d. Doubled 88. Water is a good solvent for benzoic acid recrystallization.what is the correct preparation of benzoic solution for recrystallization. a. Add benzoic acid to minimum hot water with stirring COMPILED BY: ENGR. IVAN JAN P. ROMERO | [email protected]  b. Add room temp water to benzoic while stirring until dissolved c. Add maximum hot water to benzoic acid while stirring d. Add small.portions of hot water to benzoic acid while stirring. Until dissolved 89. What is the name of RA 6969? a. Toxic Substances b. Toxic and Hazardous c. Toxic, Hazardous, and Nuclear Wastes d. Toxic, Hazardous and Nuclear Substances Note: The choices were quite confusing. The correct one should be “Toxic Substances and Hazardous and Nuclear Wastes” 90. What type of reactions is hydrogen peroxide to water and oxygen? a. Decomposition b. Replacement c. Synthesis d. Combustion 91. How to balance H2O → O2 + H2 a. Change the coefficient of O2 to 2 b. Change the coefficient of H2 to 2 c. Change the coefficients of both H2O and H2 d. Change the coefficients of both H2O and O2 to 1/2 92. What compound is possibly shown in an infrared spectrum which has peaks of 3000 cm-1 and 1650 cm-1 a. Cyclohexane b. Benzene c. Acetone d. Cyclohexene (???) 93. If you are going to mass produce vitamin C, which standard should you subscribe in? a. Both A & B b. ISO 9000 c. Both B & C d. GMP No idea since the choices were quite confusing. Maybe the choices were typo. 94. According to NFPA, what color refers to flammability. a. Blue b. Red c. Yellow d. White 95. Complete name of the acronym MSDS. a. --- b. --- c. Material Safety Data Sheet COMPILED BY: ENGR. IVAN JAN P. ROMERO | [email protected]  d. --- 96. A solution is _______ if more solute can dissolve in it. a. saturated b. supersaturated c. unsaturated d. concentrated 97. What is the molality of 6M H2SO4 solution? The density of the solution is 1.34 g/mL. (Forgot the choices haha) 98. Solutions of metals and salts are ______ a. Insulator b. Conductor c. Polar d. Negative 99. How many isomers do C5H12 have? a. 2 b. 3 c. 4 d. 5 100. Which is not a constitutional isomer of 2-butene? A. B. C. D. 101. Which of the following compounds have the same molecular and empirical formula? Choices: Different structures of carboxylic acids 107. Which of the ff are limitations of Lambert-Beer's Law? a. Scattering of light due to particles b. Fluorescence of sample c. Non-monochromatic radiation d. All of the above 108. Which of the ff requires the most energy for electronic transition? A. Alkyl halides COMPILED BY: ENGR. IVAN JAN P. ROMERO | [email protected]  B. Alkanes C. Carbonyl compounds D. Carboxylic compounds 109. The process in which the relationship of the analytical response and the concentration of the analyte is established. A. Calibration B. Standardization C. Correlation analysis D. Normalization 110. Which compound is different from compound I? A. B. C. D. 111. Which compound is different from other compounds? A. B. C. D. 112. What is the IUPAC name of the compound? A. 4-ethyl-pent-3-ene B. 2-ethyl-pent-2-ene C. 3-methyl-hex-3-ene D. 4-methyl-hex-3-ene COMPILED BY: ENGR. IVAN JAN P. ROMERO | [email protected] 113. Which compound is a tertiary alcohol? A. B. C. D. 114. What is the correct molecular formula of the molecule? A. C7H10O B. C7H12O C. C6 H8 O D. C6H10O 115. How much calcium chloride is needed to make.5L of.5M solution? 27.7 g 116. Which of the following will cause the mass of the metal block to increase? A. Putting the block in a freezer B. Heating the block C. Measuring the mass of the block in Jupiter D. None of the above 117. The process that combines alcohol and carboxylic acid to form an organic compound and water is called ____ Esterification 118. 250lb in SI unit 113 kilograms 119. When proteins are broken down by enzymes, the products are: a. amino acids b. carbohydrates c. fatty acids d. nucleic acids 120. Which of the following is an acid? A. Milk of magnesia B. Apple juice C. -- D. -- 121. Which compound will rapidly decolorize bromine in CHCl3 A. hexane COMPILED BY: ENGR. IVAN JAN P. ROMERO | [email protected]  B. benzene C. 1-hexene D. cyclohexane 122. Presence of a functional group in a compound can be established by using: a. Chromatography b. IR Spectroscopy c. Mass Spectroscopy d. X Ray diffraction 123. The gas-solid chromatography is ____________ chromatography as per basic principle involved a. Exclusion b. Ion exchange c. Adsorption d. Absorption 124. What is the advantage of using ground glass joints when carrying out a chemical reaction? a. no purities are introduced in the reactions from corks or rubber stopper b. all joints are interchangeable and a good fit is assured c. glassware apparatus can easily be assembled d. All of the above ?? 125. A compound is known to decompose at its boiling point, which of the following methods can be used to purify this substance a. Simple distillation b. vacuum distillation c. liquid-liquid extraction d. fractional distillation e. steam distillation 126. How many possible isomers of alcohol does C4H8O have? (Not sure of the exact question) 127. Which compounds have both cis and trans isomers possible? Choices: Different organic compounds were given but you can choose which one is an alkene. 128. What type of cell converts chemical to electrical energy? A. Voltaic cell B. Galvanic cell C. Electrolytic cell D. Voltaic and galvanic cells (???) Other concepts: 1. True or False questions given 3-5 different statements in an item. (This was the trickiest during the boards) 2. How to properly store HF (few questions about HF appeared) 3. Different types of blank. 4. How to add acid over water. 5. Study well about chromatography and spectroscopy (familiarize important IR absorptions). 6. Identifying the identity of the compound given its % analysis. 7. Effect of temperature and pressure on solubility of gases in liquids. COMPILED BY: ENGR. IVAN JAN P. ROMERO | [email protected]  8. Significant figures in Calculations (Rules) 9. There were two other how many types of isomer type of question I wish you success in your ChT journey! Praying, Ivan COMPILED BY: ENGR. IVAN JAN P. ROMERO | [email protected]