[ARC] Past Board Exam Flashcards
Which of the following is an extensive property of matter?
A. density
B. viscosity
C. freezing point
D. number of moles
D. number of moles
Metals and solutions of electrolytes are _____.
A. insulators
B. polar
C. negative
D. conductors
D. conductors
Mothballs are used as deodorizers and as pesticides. Upon exposing them in the air for a few hours, they disappeared. Which of the following best explains the scenario?
A. The mothballs underwent sublimation.
B. The mothballs underwent melting then vaporization.
C. The mothballs reacted with some component in the air.
D. None of the above.
A. The mothballs underwent sublimation.
Which of the following is described as having components that CANNOT be physically separated?
A. mixture
B. solution
C. suspension
D. pure substance
D. pure substance
Which of the following is TRUE for C-13 isotope?
A. It has 6 neutron and 7 protons.
B. It has 6 protons and 7 neutrons.
C. It has 6 neutron and 13 protons.
D. It has 6 protons and 13 neutrons.
B. It has 6 protons and 7 neutrons.
A prediction or a possible explanation to the question or problem which can be tested in an experiment is called
A. hypothesis
B. procedure
C. graph
D. data
A. hypothesis
Express the number 0.051065 to four significant figures.
A. 0.051
B. 0.051
C. 0.05106
D. 0.0511
C. 0.05106
The volume of a liquid is 20.5 mL. Which of the following sets of measurement represents the value with good accuracy?
A. 19.2 mL, 19.3 mL, 18.8 mL, 18.6 mL
B. 18.9 mL, 19.0 mL, 19.2 mL, 18.8 mL
C. 18.6 mL, 17.8 mL, 19.6 mL, 17.2 mL
D. 20.2 mL, 20.5 mL, 20.3 mL, 20.1 mL
D. 20.2 mL, 20.5 mL, 20.3 mL, 20.1 mL
Noble gases are inert because they have completed outer electron shells. Which of these elements is NOT a noble gas?
A. Chlorine
B. Krypton
C. Helium
D. Argon
A. Chlorine
What is the most common isotope of Hydrogen?
A. Hydrogen only has one isotope
B. Deuterium
C. Tritium
D. Protium
D. Protium
From left to right in a periodic table
A. atomic radius increases
B. ionization energy decreases
C. electronegativity increases
D. none of the above
C. electronegativity increases
Balance the following equation: Ag + O2 → Ag2O
A. Put 2 for Ag
B. Put 4 for Ag and 2 for Ag2O
C. Put subscript 2 after Ag2O
D. Put 2 for Ag and 1 for Ag2O
B. Put 4 for Ag and 2 for Ag2O
Which is NOT an acceptable name for Hg2Cl2?
A. mercury(II) chloride
B. mercury(I) chloride
C. mercurous chloride
D. dimercury dichloride
A. mercury(II) chloride
Which of the following does NOT describe a nonpolar bond?
A. It is a bond between similar nonmetals.
B. It is a bond between different nonmetals.
C. It has a dipole moment.
D. All describes a nonpolar bond.
C. It has a dipole moment.
What is the chemical formula of diphosphorus monobromide?
A. PBr2
B. PBr
C. P2Br2
D. P2Br
D. P2Br
Under the Lewis concept of acid and bases, an acid is
A. an electron pair donor
B. a proton acceptor
C. a proton donor
D. an electron pair acceptor
D. an electron pair acceptor
Which of the following is NOT an acid?
A. milk of magnesia
B. apple juice
C. milk
D. gastric juice
A. milk of magnesia
Which is NOT an acid-base conjugate pair?
A. NH₃ and NH₄⁺
B. H₂S and OH⁻
C. H₂O and OH⁻
D. HCN and CN⁻
B. H₂S and OH⁻
When ammonium chloride (NH4Cl) hydrolyzes, the resulting solution is ____.
A. acidic
B. basic
C. neutral
D. none of the choices
A. acidic
Which of the following is the correct composition of aqua regia?
A. 1 HNO3 : 3 HCl
B. 3 HNO3 : 1 HCl
C. 2 HNO3 : 3 HCl
D. 3 HNO3 : 2 HCl
A. 1 HNO3 : 3 HCl
Sodium carbonate is also known as?
A. baking soda (NaHCO3)
B. soda ash (Na2CO3)
C. caustic potash (KOH)
D. caustic soda (NaOH)
B. soda ash (Na2CO3)
The standard pressure of the atmosphere at sea level is
A. 1 atm
B. 760 mm Hg
C. 760 torr
D. all of the above
D. all of the above
Which of the following is the closest to being an ideal gas?
A. Oxygen
B. Nitrogen
C. Helium
D. Hydrogen
C. Helium
What happens to the volume of a fully inflated balloon when it is taken outside on a cold day?
A. its volume decreases
B. its volume increases
C. it remains the same
D. its volume becomes equal to zero
A. its volume decreases
What is the molar mass or an unknown gas if 1.60 grams of that gas occupies a volume of 2.24 L at STP?
A. 35.8 g/mol
B. 160 g/mol
C. 16.0 g/mol
D. 81.0 g/mol
C. 16.0 g/mol
What is the molarity of a solution containing 72.9 grams of HCI in enough water to make 500 mL of solution?
A. 2.0 mol/L
B. 4.05 g/L
C. 5.0 mol/L
D. 4.05 mol/L
D. 4.05 mol/L
The number 2.34x107 is the scientific notation
for
A. 234000
B. 23400
C. 23400000
D. 2340000
C. 23400000
When Chromium changes from an oxidation state of +3 to +6, Cr³⁺ or Cr(III) must
A. gain 6 electrons
B. lose 6 electrons
C. lose 3 electrons
D. gain 3 electrons
C. lose 3 electrons
During the electroplating of silver, silver ions in solution _____.
A. are oxidized at the anode
B. are oxidized at the cathode
C. are reduced at the cathode
D. remain in solution unchanged
C. are reduced at the cathode
In an electrolytic cell, oxidation occurs
A. at the anode
B. between the cathode and the anode
C. at either the cathode or the anode
D. at the cathode
A. at the anode
For the reaction Mg + H2O -> MgO + H2 which is FALSE?
A. H is the oxidizing agent
B. Mg lost electrons
C. Mg is the oxidizing agent
D. H gained electrons
C. Mg is the oxidizing agent
Which is also equivalent to 0.01% percent by weight?
A. 100 ppm
B. 10 ppt
C. 1 ppt
D. 1 ppb
A. 100 ppm
What volume of 4M HCl is needed to prepare 1L of a 0.5 M dilute solution?
A. 0.0125 L
B. 0.125 L
C. 0.0875 L
D. 0.875 L
B. 0.125 L
The water content of an 875.4-mg sample of cheese was determined with a moisture analyzer. What is the %w/w H2O in the cheese if the final mass was found to be 545.8 mg?
A. 35.23%
B. 30.69%
C. 31.45%
D. 37.65%
D. 37.65%
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 25C 0.99707 g/mL
A. 50.27 mL
B. 50.37 mL
C. 50.17 mL
D. 50.45 mL
A. 50.27 mL
What is the normality of a 5.0 M sulfuric acid?
A. 2.5 N
B. 5.0 N
C. 7.5 N
D. 10.0 N
D. 10.0 N
Which of the following is a primary standard for use in standardizing bases?
A. Acetic acid
B. Sulfuric acid
C. Potassium hydrogen phthalate
D. Ammonium hydroxide
C. Potassium hydrogen phthalate
The maximum holding time for acid preserved samples that will be subjected to determination of metals is
A. 48 hours
B. 3 months
C. 6 months
D. 1 week
C. 6 months
Glass container is NOT suitable for
A. oil and grease determination
B. microbiological analyses
C. all of the choices
D. inorganic trace analyses
D. inorganic trace analyses
What Is the main ISO Standard used by testing and calibration laboratories to gain accreditation and formal of their competence to carry out tests and/or calibrations, including sampling?
A. ISO/IEC 17025
B. EURACHEM
C. AOAC
D. ISO 9000:2000
A. ISO/IEC 17025
According to Revised DAO 04-36, the appropriate waste labels shall Include
A. Generator ID Number
B. Volume of Waste
C. Container Material
D. All of the above
D. All of the above
Which of the following is the most accurate apparatus in measuring 8.55 mL of liquid?
A. 1 mL graduated cylinder
B. 100 mL graduated cylinder
C. 10 mL pipet
D. 50 mL beaker
C. 10 mL pipet
Which of the following is NOT a proper laboratory practice?
A. wearing of masks and gloves
B. drying of glassware after washing
C. tying or braiding long hairs
D. adding water to strong acid
D. adding water to strong acid
Which of the following is the most appropriate container for hexane?
A. glass bottle
B. amber bottle
C. plastic bottle
D. none of these
B. amber bottle
Minimum concentration of a substance that can be measured and reported with confidence at the analyte concentration is greater than zero refers to _________.
A. Lower Warning Limit
B. Method Detection Limit
C. Control Limit
D. Limit of Quantitation
B. Method Detection Limit
The fire triangle consists of which of the following?
A. Oxygen, Heat, Material
B. Air, Heat. Fire
C. Air, Fuel, Spark
D. Oxygen, Heat, Fuel
D. Oxygen, Heat, Fuel
Which Is TRUE about laboratory hoods?
A. Provides further protection by diluting low of flammable gases below explosion limits.
B. It protects you from being exposed in chemical fume.
C. Must always be on
D. All of the above.
D. All of the above.
Which of the following focuses on Quality Management Systems?
A. IS0 9001
B. ISO 17025
C. ISO 15189
D. GLP
A. IS0 9001
There is a definite correlation between orderliness and level of safety in the laboratory. In addition, a disorderly laboratory can hinder or endanger emergency response personnel. Which of the following housekeeping rules should NOT be adhered to?
A. Never obstruct access to exits and emergency equipment.
B. Properly label and store all chemicals.
C. Store chemical containers on the floor.
D. Clean work areas, including floors, regularly.
C. Store chemical containers on the floor.
Consider that you are working with vitamin C table production, to which standard’s should your quality management should subscribe?
A. GMP
B. HACCP
C. ISO 9001:2008
D. All of the above
D. All of the above
How many significant figures does the universal gas constant (R = 0.0821 L⋅atm/mol⋅K)?
A. 3
B. 4
C. 5
D. infinite
D. infinite
How many electrons can fit in the fourth main shell?
A. 4
B. 8
C. 16
D. 32
D. 32
Which does NOT correspond to the electron configuration below?
1s² 2s² 2p⁶ 3s² 3p⁶
A. K⁺
B. C⁻
C. S²⁻
D. None of the above.
D. None of the above.
Which of the following elements has greater electron affinity than oxygen?
A. sulfur
B. carbon
C. neon
D. fluorine
D. fluorine
Which molecular geometry has the greatest bond angle?
A. linear
B. tetrahedral
C. octahedral
D. trigonal bipyramidal
A. linear
- What is the name of the compound indicated below?
Pb(CIO)₄
A. plumbous perchlorate
B. plumbic perchlorate
C. plumbous hypochlorite
D. plumbic hypochlorite
D. plumbic hypochlorite
What is the chemical formula of nitrous acid?
A. HN₃
B. HNO₂
C. HNO₃
D. H2NO₃
B. HNO₂
What is the other name for oil of vitriol?
A. paraffin
B. olefin
C. sulfuric acid
D. wax
C. sulfuric acid
From top to bottom down the periodic table
A. change in atomic radius cannot be predicted
B. ionization energy increases
C. electronegativity decreases
D. atomic radius decreases
C. electronegativity decreases
From left to right across the periodic table
A. atomic radius increases
B. ionization energy decreases
C. electronegativity decreases
D. atomic radius decreases
D. atomic radius decreases
Alcohols and carboxylic acids have –OH groups. What type of chemical bonding occurs between the oxygen and hydrogen atoms?
A. ionic
B. polar covalent
C. hydrogen
D. non-polar covalent
B. polar covalent
It is a result of instantaneous dipole in a non-polar molecule?
A. Van der Waals forces
B. Dipole-dipole interaction
C. Ion-dipole interaction
D. Hydrogen bonding
A. Van der Waals forces
Which among the following compounds has the lowest boiling point?
A. decanol
B. lauric acid
C. toluene
D. benzene
D. benzene
What IMFA is/are present in the compound indicated below?
H₃C(CH₂)₃CHO
A. Van der Waals forces only
B. Dipole-dipole interactions only
C. Van der Waals and dipole-dipole interactions
D. Van der Waals, dipole-dipole interactions, and hydrogen bonding
C. Van der Waals and dipole-dipole interactions
A cylinder containing a gas is compressed to half its original volume. What will happen to its pressure at constant temperature?
A. doubled
B. halved
C. no effect
D. cannot be determined
A. doubled
A 30-L gas initially has 110 kPa and 147°C. If its volume become 40 L and the pressure increased to 120 kPa, what is the new temperature (°C)?
A. 65
B. 214
C. 338
D. 611
C. 338
What is the pressure (atm) of hydrogen if it has 0.412 mol at 16°C in a 3.25 L?
A. 1
B. 2
C. 3
D. 4
C. 3
Nitrogen gas can be prepared by passing gaseous ammonia over solid copper (II) oxide at high temperatures. The other products of the reaction are solid copper and water vapor as shown in the reaction below:
NH₃(g)+ CuO(s)>N₂(g)+Cu(s)+H₂0(g)
If 30.5 g of NH3 is reacted with 99.7 g of CuO, how much excess reactant will remain?
A. 16.3 g
B. 14.2 g
C. 7.9 g
D. 9.1 g
A. 16.3 g
Nitrogen gas can be prepared by passing gaseous ammonia over solid copper (II) oxide at high temperatures. The other products of the reaction are solid copper and water vapor as shown in the reaction below:
NH₃(g)+ CuO(s)>N₂(g)+Cu(s)+H₂0(g)
how many grams of water vapor will be formed?
A. 48.4 g
B. 22.6 g
C. 32.3 g
D. 21.4 g
B. 22.6 g
Which of the following is a chemical reaction?
A. an air conditioner cooling the air
B. none of these choices
C. bleaching your clothes
D. melting of ice
C. bleaching your clothes
A white powder is analyzed and found to contain 43.64% phosphorus and 56.36% oxygen by mass. The compound has a molar mass of 283.88 g. What is the molecular formula of the compound?
A. P₂O₅
B. P₄O₁₀
C. P₁O₁.₃
D. P₁.₄O₃.₅
B. P₄O₁₀
How many grams of potassium dichromate is required to prepare 250 mL of 0.1 M solution of potassium dichromate? This is solution is an oxidizing agent used in organic chemistry.
A. 1.18 g
B. 7.35 g
C. 6.38 g
D. 2.94 g
B. 7.35 g
What is the molarity of 37% w/w hydrochloric acid? The density of 37% w/w HCl is 1.18 g/mL.
A. 10 M
B. 37 M
C. 12 M
D. 8 M
C. 12 M
A polar solute usually dissolves in a polar solvent and a nonpolar solute usually dissolves in a nonpolar solvent. This is
A. the solubility rule
B. the “like dissolves like” rule
C. Henry’s law
D. Hund’s rule
B. the “like dissolves like” rule
How much of a 2.0 M stock solution do you need to prepare 50 mL of a 1.0 M solution?
A. 75 mL
B. 30 mL
C. 25 mL
D. 50 mL
C. 25 mL
The synthesis of ammonia from nitrogen and hydrogen is an exothermic reaction. Which of the following will favor the formation of ammonia?
A. Decrease in temperature
B. Increase in temperature
C. Removal of nitrogen
D. Addition of ammonia
A. Decrease in temperature
Under the Brønsted-Lowry concept of acids and bases, a base is a/an
A. proton donor
B. proton acceptor
C. electron pair donor
D. electron pair acceptor
B. proton acceptor
Determine the concentration of H+ ions in apple cider vinegar if the pH was measured to 3.57.
A. 2.7 x 10⁻⁴ M
B. 3.7 x 10⁻³M
C. 5.5 x 10⁻¹ M
D. 1.3 x 10⁻¹ M
A. 2.7 x 10⁻⁴ M
The following statements are true about pH EXCEPT
A. it is the negative logarithm of hydrogen ions content in a solution
B. a measure of the acidity or alkalinity of a solution
C. a measure of the amount or hydrogen ions in solution
D. does not change when there are changes in temperature
D. does not change when there are changes in temperature
In which of the following titrations does pH = 7.0 occur at the equivalence point?
I. Strong acid/strong base
II. Weak acid/strong base
III. Strong acid/weak base
A. II and III only
B. III only
C. I only
D. II only
C. I only
A type of analysis in terms of sample size that can resolve fine-scale variations in chemical elements, as well as determine the presence and distribution of different phases in materials.
A. Macro
B. Semi-macro
C. Micro
D. Ultra-micro
C. Micro
An analyst determines that the analytical balance he used in a given analytical test is wrongly calibrated. Determine what type of error is represented.
A. Systematic error
B. Random error
C. Gross error
D. Cannot be determined
A. Systematic error
It is a plot of an instrument’s readout vs. concentration, the data for which are the results of measuring a series of standard solutions prepared for the experiment.
A. Linear range
B. Calibration curve
C. Dynamic range
D. Linear dynamic range
B. Calibration curve
It describes the policies and procedures the laboratory has to manage in relation to quality, or references where those procedures can be found. An essential requirement of ISO 9000 series of standards and ISO 17025.
A. Quality Assurance
B. Quality Control
C. Quality Manual
D. Documentation
C. Quality Manual
It is a written program developed and implemented by the employer which sets forth procedures, equipment, PPE, and work practices that are capable of protecting employees from the health hazard presented by hazardous chemicals used in the workplace.
A. Safety Manual
B. Chemical Hygiene Plan
C. Safety Rules and Policies
D. Safety Plan
B. Chemical Hygiene Plan
This type of method consists of a set of instructions about how to carry out a method issued by a national standards body and legislated by the national government to become mandatory.
A. Standard method
B. Regulatory method
C. Reference method
D. Validated method
B. Regulatory method
In starting-up laboratory operations, the following should be observed except.
A. Turning on the hoods, vents, and exhaust fans.
B. Turning the equipment and instruments on.
C. Performing analysis immediately.
D. Monitoring operating parameters.
C. Performing analysis immediately.
The following groups are known to be peroxide-forming compounds EXCEPT
A. Ethers with primary and/or secondary alkyl groups.
B. Hydrocarbons with allylic, benzylic, or propargylic hydrogens.
C. Conjugated dienes, eneynes, and diynes.
D. All are peroxide-formers.
D. All are peroxide-formers.
Which of the following is/are TRUE about the laboratory chemical hood?
I. All work should be carried out at least 15 cm (6 in.) from the front edge of the hood.
II. Before each work, be sure that the hood exhaust system is functioning properly.
III. Store hazardous chemicals inside the chemical hood to protect personnel from toxic fumes exposure.
IV. The performance of laboratory chemical hood is highly dependent on its location.
A. I and II
B. II, III and IV
C. I, II, and III
D. I, II, and IV
D. I, II, and IV
What hazards are represented by a GHS pictogram with a flame over circle symbol?
A. Flammable and self-reactive substances
B. Oxidizers, organic peroxides
C. Carcinogens
D. Explosives
B. Oxidizers, organic peroxides
It is a hazardous waste characteristic which applies to waste liquids with a flash point less than 140°C or solids capable of spontaneous combustion under normal temperature and pressure.
A. Ignitability
B. Reactivity
C. Corrosivity
D. Toxicity
A. Ignitability
What is the pH of an acidic waste?
A. pH ≤ 2
B. pH ≤ 3
C. pH ≥ 12.5
D. pH = 7
A. pH ≤ 2
This refers to a person who produces hazardous wastes, through any institutional, commercial, industrial, or trade activities.
A. Waste generator
B. Waste treater
C. Waste transporter
D. Pollution Control Officer
A. Waste generator
The correct hierarchy of control principle (decreasing
priority) from a chemical exposure perspective is
I. PPE
Il. Engineering controls
III. Administrative controls
IV. Elimination
V. Substitution
A. I>II > III > IV > V
B. I > III > II > IV > V
C. V > IV > II > III > I
D. IV > V > II > III > I
D. IV > V > II > III > I
An exposure limit that indicates the maximum average concentration to which workers can safely be exposed for a normal 8-hr workday or 48-hr workweek.
A. Time weighted average (TWA)
B. Short-term exposure limit (STEL)
C. Ceiling (C)
D. Immediately dangerous to life or health (IDLH)
A. Time weighted average (TWA)
This refers to a single sample or measurement taken at specific time or over a short period as feasible.
A. Grab sample
B. Composite sample
C. Laboratory sample
D. None of the above
A. Grab sample
The following are good sampling practices EXCEPT
A. Take several increments and composite them to form the sample.
B. If possible, mix the material before getting the sample.
C. Collect the sample in a container made of material that will chemically react with the sample.
D. Sample frequently enough to allow for the identification of process cycles.
C. Collect the sample in a container made of material that will chemically react with the sample.
Which of the following are TRUE about uncertainty?
I. It is a difference between a single measurement or result and its true value.
II. The range of possible values for a measurement.
III. A measure of bias in a result or measurement.
IV. It accounts for all errors (both determinate and indeterminate).
A. I and II
B. I and IV
C. II and III
D. II and IV
D. II and IV
It is a graph showing the time-dependent change in the results of an analysis that is used to monitor whether an analysis is in a state of statistical control.
A. Calibration curve
B. Standard Curve
C. QC chart
D. Monitoring chart
C. QC chart
A clean sample (e.g. distilled water) processed through the instrumental steps or the measurement process to determine instrument contamination.
A. Method blank
B. Instrumental blank
C. Surrogate
D. Reagent blank
B. Instrumental blank
How many significant figures are there in the 3.400 g?
A. Infinite
B. 2
C. 3
D. 4
D. 4
What is the scientific notation of 0.0078 ug/mL. of compound A?
A. 7.8 x 10⁻¹ μg/mL
B. 7.8 x 10⁻² μg/mL
C. 7.8 x 10⁻³ μg/mL
D. 7.8 x 10⁻⁴ μg/mL
C. 7.8 x 10⁻³ μg/mL
Mass ______.
A. has the SI unit of pounds.
B. is the amount of matter that occupies space.
C. is the quantitative measure of acceleration, a fundamental property of all matter.
D. constitutes the force exerted on matter by the gravitational attraction of Earth, and so it varies
slightly from place to place.
B. is the amount of matter that occupies space.
Which of the following is an extensive property of matter?
A. Density
B. Viscosity
C. Freezing point
D. Number of moles
D. Number of moles
Which will cause the mass of a metal block to increase?
A. putting it in a freezer
B. heating it
C. measure in Jupiter
D. none of the above
D. none of the above
When two materials that have different densities, like oil and water, encounter one another, they will
A. separate based on their densities
B. exchange densities
C. mix uniformly
D. repel one another
A. separate based on their densities
Which does NOT indicate a chemical change?
A. change in color
B. increase in temperature
C. change in shape
D. evolution of gas
C. change in shape
Mothballs are used as deodorizer and as pesticides. Upon exposing them in air for a few hours, they disappeared. Which of the following best explains the scenario?
A. The mothballs underwent sublimation.
B. The mothballs underwent melting then vaporization.
C. The mothballs reacted with some component in the air.
D. None of the above.
A. The mothballs underwent sublimation.
Which of the following is described as having components that can be physically separated?
A. mixture
B. solution
C. suspension
D. compound
A. mixture
It is the statement that contains the result of the experiment and checks if the hypothesis is correct or not.
A. procedure
B. hypothesis
C. conclusion
D. theory
C. conclusion
What is the most common isotope of hydrogen?
A. H has only one isotope
B. Protium
C. Deuterium
D. Tritium
B. Protium
Which of the following is TRUE for C-13 isotope?
A. It has 6 neutron and 7 protons.
B. It has 6 protons and 7 neutrons.
C. It has 6 neutron and 13 protons.
D. It has 6 protons and 13 neutrons.
B. It has 6 protons and 7 neutrons.
A certain radioisotope has a half-life of 9 days. What percentage of an initial mass of this isotope remains after 25 days?
A. 14.58
B. 0.57
C. 73.05
D. 85.41
A. 14.58
Which of the following is NOT a possible set of quantum numbers?
A. n= 3, l1 = 1, mₗ = -1, mₛ = -1/2
B. n= 3, I = 0, mₗ = 0, mₛ = -1/2
C. n = 3, I = 0, mₗ = -1, mₛ = -1/2
D. n= 3, l = 1, mₗ = 0, mₛ = -1/2
C. n = 3, I = 0, mₗ = -1, mₛ = -1/2
Which is the correct arrangement for increasing affinity for electrons?
A. K < Na < Cl < Ne
B. Na < K < Cl < Ne
C. Ne < K < Na < Cl
D. Ne < Na < K < Cl
C. Ne < K < Na < Cl
Which of the following atoms is the largest?
A. Cs
B. Sr
C. Ga
D. As
A. Cs
Which of the following oxides is likely to be basic in aqueous solution?
A. SO₂
B. CO₂
C. MgO
D. P₂O₅
C. MgO
Fluorine is capable of forming covalent bonds with which of the following element?
A. Zinc
B. Boron
C. Lithium
D. Calcium
B. Boron
Chromium is a member of which of the following?
A. Actinides
B. Lanthanides
C. Alkali metals
D. Transition metals
D. Transition metals
What is an alloy?
A. Solid solution
B. Liquid solution
C. Gaseous solution
D. All of the above
A. Solid solution
Which element is a pale-yellow gas that reacts with water?
A. H₂
B. F₂
C. Cl₂
D. Br₂
B. F₂
Which of the following is a chemical equation?
A. CO₂
B. C + O₂ ⟶ CO₂
C. Ice + Heat ⟶ Water
D. Iron + Oxygen ⟶ Rust
B. C + O₂ ⟶ CO₂
What is the name of the compound PCl₃?
A. Phosphorus chloride
B. Phosphorus trichloride
C. Phosphorus chloride(III)
D. Phosphorus trichloride(III)
B. Phosphorus trichloride
What is the chemical formula of mercurous chloride?
A. HgCl
B. Hg₂Cl
C. HgCl₂
D. Hg₂Cl₂
D. Hg₂Cl₂
Which of the following covalent compounds has a tetrahedral geometry?
A. CH₄
B. NH₃
C. H₂O
D. BF₃
A. CH₄
Which of the following does NOT describe a nonpolar bond?
A. It is a bond between similar nonmetals.
B. It is a bond between different nonmetals.
C. It has a dipole moment.
D. All describes a nonpolar bond.
C. It has a dipole moment.
Which of the following is a polar molecule?
A. CO₂
B. SF₄
C. CCl₄
D. XeF₄
B. SF₄
Which of the following statements is TRUE?
A. Double bonds are shorter than triple bonds.
B. Double bonds are stronger than triple bonds.
C. Single bonds have lower energy than double bonds.
D. None of the statements above is true.
C. Single bonds have lower energy than double bonds.
Polar molecules include which of these?
I. CO₂
II. COCI₂
III. CH₂Cl₂
A. I only
B. I and II only
C. I and III only
D. II and III only
D. II and III only
Which compound has the strongest intermolecular force of attraction?
A. CO
B. CH₄
C. CH₃OH
D. CH₃OCH₃
C. CH₃OH
Which of the following is NOT an indication of strong IMFA?
A. high viscosity
B. high volatility
C. high boiling point
D. high melting point
B. high volatility
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
B. 50.27 mL
At 25°C a gas expands from 30 kPa and 5.0 L to 70°C and 10 kPa. Calculate its final volume.
A. 17 L
B. 24 L
C. 42 L
D. 71 L
A. 17 L
What is the density of oxygen at 1 atm and 25°C?
A. 1.31 g/mL
B. 1.31 g/L
C. 15.6 g/mL
D. 15.6 g/L
B. 1.31 g/L
Each of these flasks contains the same number of molecules. In which container is the pressure highest?
(flask in increasing volume)
A. flask 2
B. flask 1
C. flask 3
D. flask 4
B. flask 1
What happens to the volume of a fully inflated balloon when it is taken outside on a cold day?
A. Its volume decreases
B. It remains the same
C. Its volume increases
D. Its volume becomes equal to zero
A. Its volume decreases
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
A. the solubility of gases in water decreases with increasing temperature
- Liquid A has lower boiling point than liquid B. Which of the following is true about the boiling point of the solution formed upon mixing A and B?
A. less than that of A
B. greater than that of B
C. average of A and B
D. between A and B
D. between A and B
It is the temperature at which solid and liquid coexist.
A. melting point of liquid
B. freezing point of liquid
C. freezing point of solid
D. all of the above
B. freezing point of liquid
- All solid states are denser than their liquid states. However, water is unique because
A. It is clear.
B. It is tasteless.
C. Its solid form (ice) is less dense than its liquid form.
D. It can freeze.
C. Its solid form (ice) is less dense than its liquid form.
How many atoms does a kilogram of copper (63.55 g/mol) metal have?
A. 9.5x10²¹
B. 9.5x10²⁴
C. 3.8x10²¹
D. 3.8x10²⁴
B. 9.5x10²⁴
An analysis of a compound shows 62.04% C, 10.41% H, and 27.55% O. Which of the following is the most probably identity of the compound?
A. C₂H₄O
B. C₂H₄O₂
C. C₃H₆O
D. C₃H₆O₂
C. C₃H₆O
A 1.00 g sample of which compound will produce the greatest amount of carbon dioxide after complete combustion with excess oxygen?
A. CH₄
B. C₃H₆
C. C₆H₁₄
D.C₈H₁₈
B. C₃H₆
Which procedure produces a 0.2 M solution of Na2SO4?
A. Mixing 500 mL of 0.4 M NaOH with 500 mL of 0.2 M Na2SO4
B. Mixing 300 mL of 1.2 M NaOH with 600 mL of 0.3 M Na2SO4
C. Dissolving 0.2 M solid Na2SO4 in 500 mL water
D. Diluting 400 mL of 0.3 M Na2SO4 to a final volume of 1.0 L
B. Mixing 300 mL of 1.2 M NaOH with 600 mL of 0.3 M Na2SO4
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
B. A catalyst speeds up both the forward and reverse reaction rates.
- A solution is _______ if more solute can dissolve in it.
A. saturated
B. supersaturated
C. unsaturated
D. concentrated
C. unsaturated
A solution contains 34.0% HClO4 by mass. HClO4 has a molar mass of 100.45 g/mol. The solution has a density of 1.242 g/mL. What is the molar concentration of this solution?
A. 5.13 M
B. 4.20 M
C. 8.40 M
D. 0.916 M
B. 4.20 M
A solution has been prepared by transferring 60 mL of 85% by volume H3PO4 and diluting i to 1.0 L. What is the concentration of the new solution?
A. 10.10%
B. 9.25%
C. 12.2%
D. 5.10%
D. 5.10%
Which of the following substances is not basic?
A. Baking soda
B. Apple Juice
C. Borax
D. Seawater
B. Apple Juice
A 2.4 L of HNO3 solution reacts with 63 mL of 1.9 N Ba(OH)2 to produce a neutral solution. What is the molar concentration of the original HNO3 solution?
A. 0.05 M
B. 0.12 M
C. 0.24 M
D. 0.50 M
A. 0.05 M
The following statements are TRUE about pH EXCEPT
A. It is the negative logarithm of hydrogen ions content in a solution.
B. It is a measure of the acidity or alkalinity of a solution.
C. It is a measure of the amount or hydrogen ions in solution.
D. It does not change when there are changes in temperature.
D. It does not change when there are changes in temperature.
A solution is prepared by adding 0.1 M H2CO3 and 0.1 M NaHCO3. 0.01 mole HCl is added to 1 liter of the prepared solution. The pH of the resulting is close to? The pKa of H2CO3 is 6.37.
A. 6.28
B. 4.90
C. 5.21
D. 6.37
A. 6.28
When NaCH3COO hydrolyzes, the resulting solution is
A. acidic
B. basic
C. neutral
D. none of the above
B. basic
When a strong acid reacts with a weak base during titration, the pH at the equivalence point is
A. basic
B. acidic
C. neutral
D. none of the above
B. acidic
- A lab analyst dissolved 4.021 g of NaOH in water and made up the solution to 1L with water. He then pipetted 10.00 mL of this solution into a flask and titrated it with 0.050 M HCI solution from a burette. A volume of 20.32 mL of acid had been used at the endpoint. Examining this
result, the lab supervisor could deduce that _____.
A. the NaOH absorbed H2O from the air after its mass was measured
B. the burette was rinsed with water instead of HCI
C. the analysis is as accurate as can be expected using this apparatus
D. the pipette was rinsed with water instead of NaOH
B. the burette was rinsed with water instead of HCI
The Kjeldahl method is the worldwide standard for calculating the protein content in a wide
variety of materials ranging from human and animal food, fertilizer, waste water and fossil fuels. It consists of three steps: digestion, distillation, and titration. What element is being analyzed in Kjeldahl method?
A. Carbon
B. Nitrogen
C. Sulfur
D. Oxygen
B. Nitrogen
- In a galvanic cell, reduction occurs in the ____ while in an electrolytic cell, oxidation occurs in the ____.
A. anode, anode
B. cathode, cathode
C. cathode, anode
D. anode, cathode
C. cathode, anode
Conductivity is the ability of a substance to
A. conduct electric current, which is the same as resistivity.
B. repel electric current.
C. conduct variable resistance.
D. conduct electric current, which is the reciprocal of resistivity.
D. conduct electric current, which is the reciprocal of resistivity.
Column chromatography is based on the principle of _____________.
A. Exclusion
B. Absorption
C. Ion exchange
D. Differential adsorption
D. Differential adsorption
Which of the following statements is correct?
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. None of the above.
C. The greater the polarity of solute, more strongly it will be adsorbed on a polar surface.
The components of the mixture in column chromatography are eluted in order of
A. increasing polarity and decreasing distribution ratio
B. increasing polarity and increasing distribution ratio
C. decreasing polarity and increasing distribution ratio
D. decreasing polarity and decreasing distribution ratio
B. increasing polarity and increasing distribution ratio
Why is it generally preferable to use absorbance as a measure of absorption rather than % transmittance?
A. because %T cannot be measured as accurately as absorbance
B. because %T is dependent on the power of the incident radiation
C. because absorbance is proportional to the concentration of the analyte, whereas %T is not
D. none of the above
C. because absorbance is proportional to the concentration of the analyte, whereas %T is not
What will you perform to know that atomic absorption spectrometer continues to work property?
A. Calibration check
B. Blank
C. QC sample recoveries
D. Standard addition
A. Calibration check
A student wants to improve the accuracy of a 9.40 mL liquid using a 100 mL graduated cylinder. Which of the following should he do?
A. take the average of multiple measurements
B. add an additional significant figure
C. use 25 mL graduated cylinder instead
D. use 10 mL graduated cylinder instead
D. use 10 mL graduated cylinder instead
Statistical test that decides whether a datum from a given set could be rejected or NOT is the ______.
A. t-test
B. z-test
C. Q-test
D. F-test
C. Q-test
An analysis of ore assays about 1.5% iron. What minimum sample mass should be taken if the relative error resulting from a 0.5-mg loss is not to exceed -0.2%?
A. 16.7 mg
B. 17 mg
C. 17 g
D. 16 g
C. 17 g
For a concentration technique, the relationship between the measure signal, Smeas and the analyte’s concentration, CA, is given by equation Smeas = kCA + Sb. Given the Smeas is 24.37 ± 0.02, Sh is 0.96 ± 0.02, and k is 0.186 ± 0.003 ppm-1
Calculate for the percent relative uncertainty for the analyte’s concentration.
A. 0.0162
B. 1.6
C. 0.0264
D. 2.6
B. 1.6
For a concentration technique, the relationship between the measure signal, Smeas and the analyte’s concentration, CA, is given by equation Smeas = kCA + Sb. Given the Smeas is 24.37 ± 0.02, Sh is 0.96 ± 0.02, and k is 0.186 ± 0.003 ppm-1
Report the absolute uncertainty together with the analyte’s concentration.
A. (125.9 ± 3.3) ppm
B. (126 ± 3) ppm
C. (125.9 ± 2.0) ppm
D. (126 ± 2) ppm
D. (126 ± 2) ppm
Which of the following focuses on Quality Management Systems?
A. ISO 9001
B. ISO 17025
C. ISO 15189
D. GLP
A. ISO 9001
It is a part of quality system that includes laboratory operations whose objective is to ensure that the data generated by the laboratory are of known accuracy to some stated, quantitative degree of probability.
A. Quality Management
B. Quality Assurance
C. Quality Control
D. Quality Manual
C. Quality Control
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
B. Matrix spike
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
B. selective sampling
The quantity of material which is assumed to represent a single population for sampling purposes.
A. Bulk material
B. Lot
C. Segment
D. Batch
B. Lot
What is the name of RA 6969?
A. Toxic Substances Control Act
B. Toxic Substances and Hazardous Wastes Control Act
C. Toxic Substances and Hazardous and Nuclear Wastes Control Act
D. Toxic Substances and Hazardous and Nuclear Wastes Management Control Act
C. Toxic Substances and Hazardous and Nuclear Wastes Control Act
The responsibilities of chemists and chemical technicians embodied in the Code of Ethics include all EXCEPT
A. They are expected to be stewards of the environment by following the laws, rules and regulations pertaining to chemical wastes management and disposal.
B. They shall undertake the professional practice of Chemistry only when in possession of a valid COR and ID issued by the Board and the Commission.
C. All Chemistry practitioners are obliged to maintain active membership in the Accredited Professional Organization (APO) for the Chemistry profession, and to participate in the activities of the latter.
D. None of the above.
D. None of the above.
Type of analysis where the amounts of all constituents in the samples are determined.
A. Complete (or ultimate) analysis
B. Partial analysis
C. Elemental analysis
D. Proximate analysis
A. Complete (or ultimate) analysis
Method consisting a set of instructions issued by a national standards body.
A. Standard method
B. Primary method
C. Regulatory method
D. Validated method
A. Standard method
It is a detailed written instruction to achieve uniformity in the performance of a specific function.
A. Standard method
B. Protocol
C. Standard operating procedure
D. Analytical procedure
C. Standard operating procedure
Which of the following correctly describe/s the detection limit?
I. Concentration that gives a readout level that is more than the electrical noise level inherent in the baseline.
II. It is the smallest concentration that can be determined with a reasonable degree of precision.
III. A qualitative parameter in the sense that it is the minimum concentration that can be detected, but not precisely determined.
IV. It would tell the analyst that the element is present, but not necessarily at a precisely determinable concentration level.
A. II and III
B. I, III, and IV
C. II, III, and IV
D. III only
B. I, III, and IV
Analytical methods or instruments’ performance aim for
A. Low signal-to-noise ratio
B. High variability
C. Low dynamic range
D. High signal-to-noise ratio
D. High signal-to-noise ratio
- It accounts for all the other components in the mixture that are not under investigation.
A. Analyte
B. Matrix
C. Measurand
D. Test
B. Matrix
When qualifying a working standard, what is the best type of reagent to use?
A. Reagent grade
B. Technical grade
C. Primary standard
D. Analytical grade
C. Primary standard
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
D. All of the above
According to Revised DAO 04-36, the appropriate waste labels shall Include
A. Generator ID Number
B. Volume of Waste
C. Container Material
D. All of the above
D. All of the above
Which of the following is the most appropriate container for hexane?
A. glass bottle
B. amber bottle
C. plastic bottle
D. none of these
B. amber bottle
What type of container should be used when handling or storing hydrogen fluoride?
A. Glass
B. Polyethylene
C. Cast iron
D. Alloys containing silica
B. Polyethylene
The following acids and acid mixtures can be collected and placed in glass containers EXCEPT for
A. Sulfuric acid
B. Hydrofluoric acid
C. Aqua regia
D. Hydrochloric acid
B. Hydrofluoric acid
Glass container is NOT suitable for
A. oil and grease determination
B. microbiological analyses
C. all of the choices
D. inorganic trace analyses
D. inorganic trace analyses
Ammonia solution can be stored with the following chemicals EXCEPT
A. cyclohexane solution
B. acetic acid solution
C. 2-propanol solution
D. sodium hydroxide solution
B. acetic acid solution
When working with concentrated acids except hydrofluoric acid, which of the following
statements are TRUE?
I. Gloves covering the whole arm or nitrile gloves should be worn.
II. Half- or full-faced masks with gas- and/or vapor removing respirators should be worn
III. Wearing safety boots or foot covering is optional as long as tie person is working under the hood.
IV. Wearing of apron is optional as long as laboratory gown is worn.
A. I and II
B. II and III
C. All of the choices
D. I and IV
A. I and II
Which of the following is NOT a proper laboratory practice?
A. wearing of masks and gloves
B. drying of glassware after washing
C. tying or braiding long hairs
D. adding water to strong acid
D. adding water to strong acid
Which of the following is a treatment for HF burns?
A. water
B. Epsom salt
C. 25% brine solution
D. calcium gluconate
D. calcium gluconate
- If a fire extinguisher has a red body and a blue band, what is its content?
A. Foam type
B. Dry chemical type
C. Carbon dioxide
D. Halon substitute
A. Foam type
The following are proper practices in storing materials and equipment EXCEPT ONE.
A. Avoid storing materials and equipment on top of cabinets.
B. Label all materials properly.
C. Store hazardous chemicals inside the fumehood.
D. Do not expose stored chemicals to heat or direct sunlight.
C. Store hazardous chemicals inside the fumehood.
