GenChem and AnalChem Mixed Concepts Flashcards by Board Exam Purposes

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.

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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

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Which of the following is TRUE?

A. Compounds have only one type of atom. dig
B. Elements can be chemically decomposed.
C. Solutions are considered as pure substances.
D. Heterogeneous mixtures have phase boundaries.

D. Heterogeneous mixtures have phase boundaries.

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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. It underwent sublimation.
B. It melted then vaporized.
C. It reacted with something in the air.
D. None of the above.

A. It underwent sublimation.

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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

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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

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Which of the following is an intensive property?

A. density
B. melting point
C. electric potential
D. all of the above

D. all of the above

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The standard pressure of the atmosphere at sea level is

A. 1 atm
B. 760 mmHg
C. 760 torr
D. all of the above

D. all of the above

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What is the molar mass of an unknown gas if 1.60 g of the 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

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Which of the following is TRUE for C-13 isotope?

A. It has 6 neutrons and 7 protons.
B. It has 6 protons and 7 neutrons.
C. It has 6 neutrons and 13 protons.
D. It has 6 protons and 13 neutrons.

B. It has 6 protons and 7 neutrons.

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What is the most common isotope of Hydrogen?

A. Hydrogen only has one isotope
B. Deuterium
C. Tritium
D. Protium

D. Protium

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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

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Which of the following atoms is the largest?
A. Cesium
B. Strontium
C. Gallium
D. Arsenic

A. Cesium

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Chromium is a member of which of the following?
A. Actinides
B. Lanthanides
C. Alkali metals
D. Transition metals

D. Transition metals

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Fluorine is capable of forming covalent bonds with

A. Zinc
B. Boron
C. Lithium
D. Calcium

B. Boron

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Noble gases are unreactive because they have complete outer electron shells. Which of the
the following elements is NOT a noble gas?

A. Chlorine
B. Krypton
C. Helium
D. Argon

A. Chlorine

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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

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What is the chemical formula of diphosphorus monobromide?

A. PBr2
B. PBr
C. P2Br2
D. P2Br

D. P2Br

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Sodium carbonate is also known as?

A. baking soda
B. soda ash
C. caustic potash
D. caustic soda

B. soda ash

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All of these elements are strict followers of the octet rule, EXCEPT

A. Boron
B. Carbon
C. Nitrogen
D. Oxygen

A. Boron

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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 describe a nonpolar bond.

C. It has a dipole moment.

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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.

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Which of the following covalent compounds has a tetrahedral geometry?

A. CH4
B. NH3
C. H2O
D. BF3

A. CH4

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Which of the following is a polar molecule?

A. CO2
B. SF4
C. CCl4
D. XeF4

B. SF4

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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

What is the principal intermolecular force that must be overcome when hexane is vaporized? A. Hydrogen bonding B. Covalent bonding between carbons C. Dipole-dipole forces D. London dispersion forces

D. London dispersion forces

Which compound has the strongest intermolecular forces of attraction? A. CO B. CH4 C. CH3OH D. CH3OCH3

C. CH3OH

A polar solute dissolves in a polar solvent and a nonpolar solute dissolves in a nonpolar solvent. This is the A. Hund's rule B. Henry’s law C. solubility rule D. 'like dissolves like' rule

D. 'like dissolves like' rule

Tin(II) fluoride (156.7 g/mol) is often added to toothpaste as an ingredient to prevent tooth decay. What is the mass of fluoride (19 g/mol) in 24.6 g of tin (II) fluoride? A. 0.31 g B. 2.98 g C. 5.97 D. 101.4 g

C. 5.97 g

The empirical formula of a compound is CH. The molar mass of the compound is 78 g/mol, what is its molecular formula? A. C2H2 B. C6H6 C. C8H8 D. None of the above

B. C6H6

Consider the combustion of butane C4H10 + O2 = CO2+ H2O where in a particular reaction, 5 mol of C4H10 are reacted with an excess of O2. Calculate the mol of CO2 formed. A. 1.25 mol B. 10 mol C. 12.5 mol D. 20 mol of CO2

D. 20 mol

A 1.00-g sample of which compound will produce the greatest amount of CO2 after combustion with excess oxygen? A. CH4 B. C3H6 C. C6H14 D. C8H18

B. C3H6

Ammonia is produced according to the equation N2+ 3H2 → 2NH3. In a particular experiment, 0.25 mol of NH3 is formed when 0.5 mol of N2 is reacted with 0.5 mol of H2. What is the percent yield? A. 75% B. 50% C. 33% D. 25%

A. 75%

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

For which compound are the empirical and molecular formulas the same? A. C6H5COOH B. C6H4(COOH)2 C. HOOCCOOH D. CH3COOH

A. C6H5COOH

Which of the following can change the value of the equilibrium constant? A. addition of a catalyst B. change in temperature C. change in concentration D. change in pressure or volume

B. change in temperature

Which statement is TRUE? A. The greater the activation energy, the faster the rate of reaction. B. A catalyst speeds up both the forward and reverse reaction rates. C. The value of the equilibrium constant increases with the addition of a catalyst. 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. unsaturated C. supersaturated D. concentrated

B. unsaturated

How many grams of NaOH (40 g/mol) is needed to prepare 500 mL of 0.500 N solution of NaOH? A. 4.00 g B. 5.00 g C. 10.0 g D.10.3 g

C. 10.0 g

The lining of the stomach contains cells that secrete a solution of HCI. Which drink would best alleviate heartburn, i.e., excess acid in the stomach? A. diet soda (pH 4.3) B milk of magnesia (pH 10.5) C. milk (pH 6.5) D. wine (pH 3.8)

B milk of magnesia (pH 10.5)

Which of the following 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-

The acid secreted by the cell of the stomach lining is a hydrochloric acid contains 1.2x10-3 M. What is the pH of the acid in the stomach? A. 1.50 B. 2.92 C. 3.50 D. 6.19

B. 2.92

When ammonium chloride undergoes ionization, the resulting solution will have a pH A. <7 B. 7 C. >7 D.14

A. <7

Which of these conjugate acid-base pairs must be used to prepare a buffer with pH near 7.15? A. formic acid and sodium formate (pKa 3.74) B. succinic acid and sodium succinate (pKa 5.64) C. glycylglycine and sodium glycylglycate (pK, 8.35) D. sodium dihydrogen phosphate and sodium hydrogen phosphate (pKa2 7.20)

D. sodium dihydrogen phosphate and sodium hydrogen phosphate (pKa2 7.20)

What are the products for the reaction between HNO3 and NH4OH? A. HNO2 + H2O B. NH2OH + H2O C. NH4NO3 + H2O D. No reaction will occur

C. NH4NO3 + H2O

In NaH, what is the oxidation state of hydrogen? A. -1 B. 0 C. 1 D. 2

A. -1

When Cr3+ changes from an oxidation state of +3 to +6, Cr3+ will A. gain 6 electrons B. lose 6 electrons C. lose 3 electrons D. gain 3 electrons

C. lose 3 electrons

Reduction involves ____ oxidation number. A. increase of B. decrease of C. independence of D. no change in

B. decrease of

For the reaction Mg + H2O→ MgO + H2, which is FALSE? A. H2O is the oxidizing agent B. Mg lost electrons C. Mg is the oxidizing agent D. H2O gained electrons

C. Mg is the oxidizing agent

Oxidation is the same as A. addition of hydrogen B. removal of oxygen C. addition of oxygen D. removal of Nitrogen

C. addition of oxygen

It is an electrochemical cell where electrical energy is used to drive a nonspontaneous redox reaction. A. Daniell cell B. Voltaic cell C. Galvanic cell D. Electrolytic cell

D. Electrolytic cell

Which part of an electrochemical cell maintains electrical neutrality? A. anode B. salt bridge C. cathode D. voltmeter

B. salt bridge

In an electrolytic cell, oxidation occurs A. at the anode B. at the cathode C. at either the cathode or the anode D. between the cathode and the anode

A. at the anode

During 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 maintenance and storage of pH meters, which of the following must NOT be done? A. Use a mild soap solution in general cleaning of electrodes. B. Store the electrode in distilled water to keep the electrode bulb moist during storage C. Blot electrode dry after rinsing the pH electrode. D. Rinse pH electrode in between measurements.

B. Store the electrode in distilled water to keep the electrode bulb moist during storage

Which of the following statements best describes a primary method? I. Set of instructions about how to carry out a method issued by a national standards body. II. It has the highest metrological qualities. III. Method that employs the use of materials such as certified reference materials. IV. Titration of hydrochloric acid with anhydrous sodium carbonate to determine the concentration of the acid is an example of this method. A. I only B. II only C. II and IV D. I and IV

C. II and IV

It is the fraction of the named material present in the stated chemical form. A. Potency B. Purity C. Stability D. Activity

B. Purity

If you reported that a sample with 9 mg/L of a substance has only 5 mg/L and the acceptable limit according to standard is 7 mg/L, this is A. false positive B. false negative C. accurate D. precise

B. false negative

It is a performance parameter that could be used to analyze a blank sample matrix. A. Bias estimate B. Selectivity C. Limit of quantification D. Limit of detection

D. Limit of detection

Which of the following factors affects the choice of analytical methods? A. The type of analysis required B. The accuracy required C. Possible interferences from components of the material other than those of interest. D. All of the above

D. All of the above

Which chemical grade is commonly used for low-grade applications such as cleaning and qualitative testing? A. USP Grade B. NF Grade C. Technical Grade D. Laboratory Grade

C. Technical Grade

Consider the analysis of the determination of sugar concentration in powdered juice dissolved in water. Which of the following is the matrix? A. Sugar B. Powdered juice C. Water D. B and C

D. B and C

Which of the following statement(s) is (are) TRUE about instrumental background signals? I. Even when no sample is being analyzed, the instrument will generate a background signal. II. LOD for an instrument improves if the S/N can be increased. III. LOD for an instrument is not affected by S/N. A. I only B. I and II C. I and III D. I, II, and III

B. I and II

The portion of the calibration curve which includes the range of concentrations of analyte that can be determined with demonstrated precision, accuracy, and response function. A. Limit of Detection B. Limit of Quantitation C. Working range D. Linear dynamic range

C. Working range

The property of an analytical method to determine simultaneously several components independently from each other. A. Selectivity B. Specificity C. Sensitivity D. Ruggedness

A. Selectivity

It is a part of quality systems that is officially defined by the ISO as the assembly of all planned and systematic actions to provide adequate confidence that a product, proves or service will satisfy the given quality requirements. A. Quality Management B. Quality Assurance C. Quality Control D. Quality Manual

B. Quality Assurance

This quality system standard is a general requirement for the competence of testing and calibration laboratories. A. GLP B. GMP C. ISO 9001 D. ISO/IEC 17025

D. ISO/IEC 17025

If you are going to mass produce vitamin C, which standard should you subscribe to? A. GMP B. HACCP C. ISO 9001 D. All of these

D. All of these

Which of the following statement(s) is (are) TRUE about Quality Assurance? I. Quality Assurance is a set of activities for ensuring quality in the process by which products are developed. II. Quality Assurance is a corrective tool and product oriented. A. I only B. II C. Both I and II D. None of these

A. I only

A drug sample contains 10.0 μg/L of its active ingredient. A 5.0 μg/L of spike was added to a replicate portion of the drug. The spiked sample gave a concentration of 14.6 μg/L. What is the %recovery of the spike? A. 34 B. 96 C. 37 D. 92

D. 92

Which of the following observation(s) will require a process to stop immediately? I. Results lie outside action limits II. Three consecutive measurements on one side of the central limit III. Seven consecutive measurements create an increasing trend IV. A measurement is within warning limits A. I only B. I and III C. I, II, and IV D. I, III, and IV

B. I and III

When a deviation from critical limits happens, what should be done? A. Documentation of corrective actions B. Stop the process and inform the supervisor C. Reassess the standards being implemented D. All of these

D. All of these

A type of blank that is commonly used with techniques such as spectrophotometry to zero the instrument before measuring test samples and other blanks. A. Reagent blank B. Method blank C. Trip blank D. Field blank

A. Reagent blank

Which of the following are characteristics of a QC sample? A. Similar in composition to the types of samples normally examined B. Must be stable C. Must be available in large quantities D. All of these

D. All of these

A reactive part of the quality management system that is concerned with the quality of the product, especially those materials that are soon to be released to the customer. A. Quality Assurance B. Quality Control C. Quality Audit D. Quality Evaluation

B. Quality Control

When exposure to hazards cannot be engineered completely out of normal operations and admin controls are deemed ineffective, this supplementary method of control can be used. A. Elimination B. Substitution C. Administrative control D. Use of PPE

D. Use of PPE

The area surrounding a safety shower/eyewash___. A. can be used to store boxes if they can be removed quickly B. must remain clear of all items C. is typically marked with yellow and black floor tape as a reminder to keep it clear D. Both B and C

D. Both B and C

Laboratory chemical hoods are best placed in a location that is A. near the aisle for ease of access. B. near the windows and doors C. away from air diffuser D. None of these

C. away from air diffuser

Which of the following statement(s) is (are) GOOD practices when using lab chemical hood? I. Place chemical sources and apparatus at least 6 cm behind the face. II. Scrubbers must be installed especially when the lab is dealing with highly toxic vapors. III. Avoid opening and closing the sash rapidly. IV. Store odoriferous materials inside the chemical hood to prevent personnel from inhaling the toxic vapors. A. I, and II B. I, II, and III C. III, and IV D. II, and III

D. II, and III

Which of the following is NOT a GHS pictogram? A. Exploding bomb B. Gas tank C. Skull and crossbones D. Health hazard

B. Gas tank

How long should you rinse the affected area in an eyewash during accidental chemical splashes on the eyes? A. 5 mins B. 10 mins C. 15 mins D. 30 seconds

C. 15 mins

Common hazards posed by different chemicals in the laboratories can be found at A. CHP B. SDS C. GHS labels D. All of these

D. All of these

At this concentration, the mixture of flammable liquids is considered too "lean" to burn. A. at lower explosion limit B. below lower explosion limit C. above upper explosion limit D. between upper and lower limit

B. below lower explosion limit

According to the Department of Trade and Industry-Bureau of Philippine Standards (DTI- BPS), what color designations correspond to a foam type fire extinguisher? A. red body, white band B. red body, black band C. red body, blue band D. light green body, white band

C. red body, blue band

The fire extinguisher mentioned above is most appropriately used for which type of fire? A. Fires involving ordinary combustible materials B. surface fire C. electrical fire D. Both A and B

D. Both A and B

This general type of reaction results in sudden rapid rise in temperature upon heating of the material that usually becomes violent. A. vigorous reaction B. combustion reaction C. runaway reaction D. reaction under pressure

C. runaway reaction

Which of the following functional groups pose explosion hazards? I. Azide II. Peroxide III. Thiol IV. Hydrocarbons A. I and II B. II and III C. III and IV D. I, II, and III

A. I and II

During a mercury spillage in the laboratory, what is the most appropriate action to do? A. Wipe mercury spill with dry cloth. B. Clean spill with an aspirator bulb. C. Smother the spill with powdered graphite. D. Use calcinated absorbent product such as Oil-Dri or Zorball.

B. Clean spill with an aspirator bulb.

What are the components of the fire triangle? A. oxygen, heat, material B. oxygen, fuel, heat C. air, fuel, spark D. air, fuel, fire

B. oxygen, fuel, heat

These materials ignite due to the rapid oxidation by oxygen or moisture in the air. A. Water reactive substances B. Pyrophoric substances C. Explosives D. Flammables

B. Pyrophoric substances

The following are gases under pressure EXCEPT A. Aerosols B. Liquefied gases C. Compressed gases D. All are gases under pressure

A. Aerosols

It refers to the production of reversible damage to the skin occurring after exposure to a substance or mixture. A. Skin allergy B. Skin corrosion C. Skin irritation D. Skin necrosis

C. Skin irritation

These are solid particles of a substance or mixture suspended in a gas (usually air). A. Fog B. Dusts C. Mists D. Vapor

B. Dusts

Which of the following can be best used to handle liquid acid spills? A. Soda ash B. Aspirator bulb C. Activated charcoal D. Acetic acid

A. Soda ash

This type of toxins in the chemical laboratory may potentially cause allergies or allergic-like reactions. A. Allergen B. Corrosive substance C. Sensitizer D. Asphyxiants

A. Allergen

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

A colorless liquid and a yellowish liquid were mixed in a test tube. Which of the following statements is FALSE? A. There will be no reaction if the test tube will get hot. B. There will be a reaction if a precipitate will be formed. C. There will be no reaction if the liquids will be on top of each other. D. There will be a reaction if the yellow color will drastically disappear.

A. There will be no reaction if the test tube will get hot.

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 full 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 name of Cu2O? A. Dicopper monoxide B. Cupric oxide C. Copper(I) Oxide C. Copper(II) Oxide

C. Copper(I) Oxide

Which of the following does NOT follow octet rule? A. CH4 B. CCl C. HCI D. NO2

D. NO2

What is the shape of the molecule NH3? A. Square pyramidal B. V-shape C. Trigonal pyramidal D. Tetrahedral

C. Trigonal pyramidal

Which of the following molecules geometry is TRUE? A. BrF5: Trigonal pyramidal B. CIF3: T-shaped C. PCl5: See-saw D. SF4: Trigonal bipyramidal

B. CIF3: T-shaped

Which of the following molecules has a net dipole movement? A. N2 B. CH4 C. BeF2 D. H2O

D. H2O

HCI possess(es) which of the following intermolecular interactions? A. Hydrogen bonds B. London dispersion forces only C. Dipole-dipole forces only D. London dispersion forces and dipole-dipole forces

D. London dispersion forces and dipole-dipole forces

Metals and solutions of electrolytes are A. insulators B. polar C. negative D. conductors

D. conductors

Under the Lewis definition of acid and bases, an acid is a(an). A. electron pair donor B. proton acceptor C. proton donor D. electron pair acceptor

D. 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 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 dynamic range in analytical measurement refers to the range where A. the detection limit lies B. the instrument reading is constant is C. the sensitivity of the instrument is highest D. instrument reading linear to the input value

A. the detection limit lies

It is a non-negative parameter characterizing the dispersion of the quantity values being attributed to a measurand, based on the information used. A. Measurement uncertainty B. Accuracy C. Error D. Precision

A. Measurement uncertainty

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

The main ISO Standard used by testing and calibration laboratories to gain accreditation and formalize 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 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 flammable gases below explosion limits. B. It protects you from being exposed to chemical fumes. 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. ISO 9001 B. ISO 17025 C. ISO 15189 D.. GLP

A. ISO 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 should your quality management subscribe? A. GMP B. HACCP C. ISO 9001:2008 D. All of the above

D. All of the above

Sampling type that eliminates questions of bias in selection. A. Composite B. Stratified C. Systematic D. Random

D. Random

This system is used in the food industry to identify and control potential hazards (i.e. biological, chemical, and physical) that could compromise food safety. A. GLP B. GMP C. HACCP D. ISO 9001

C. HACCP

First consideration for chemical storage shall be based on its A. frequency of usage B. compatibility with other chemicals C. size of container D. alphabetical order

B. compatibility with other chemicals

In labeling commercially packaged chemicals, the following are correct EXCEPT A. The label usually includes the name of the chemical and any necessary handling and hazard information. B. The label includes the CAS registry number to avoid ambiguity about chemical names. C. The label is supplemented by the date received. D. Replace the existing labels on incoming containers of chemicals and other materials to avoid confusion.

D. Replace the existing labels on incoming containers of chemicals and other materials to avoid confusion.

Waste is A. a material that has no intended use or reuse B. a material that has a lapsed expiration date C. any material that has been processed D. a material that has no current use

A. a material that has no intended use or reuse

The total error of an analytical result is the sum of A. sampling 8. sample preparation C. analytical errors D. all of the above

D. all of the above

Process by which a sample population is reduced in size to an amount of homogeneous material that can be conveniently handled in the lab in which the composition is representative of the population. A. Selection B. Monitoring C. Sampling D. Segregation

C. Sampling

The method of standardization can be used if a ______ reacts quantitatively with the reagent needed in the standard solution. A. primary standard B. secondary standard C. working standard D. intermediate solution

A. primary standard

During acid spills, which of the following can be applied to the spill before treating it with adsorbent material? A. Sodium bicarbonate B. Water C. Acetic acid D. Sodium

A. Sodium bicarbonate

These are any waste materials that can be retrieved from the waste stream and free from contamination that can still be converted into suitable beneficial use. A. Recyclable wastes B. Residual wastes C. Compostable wastes D. Special wastes

A. Recyclable wastes

Symbols indicated in waste labels that instantly identify the kind of hazard the chemical possesses. A. Signal words B. Pictograms C. Precautionary statements D. Hazard statements

B. Pictograms

All of the following are true EXCEPT a. Most salts increase solubility when heated b. Salt crystallizes out when the solvent is evaporated c. An endothermic dissolution process will produce more crystals when cooled d. An exothermic dissolution process will produce more crystals when cooled

d. An exothermic dissolution process will produce more crystals when cooled

Which of the following is the anhydrous form of phosphoric acid? a. H2PO3 b. HPO3 c. P2O5 d. H3PO3

c. P2O5

Which of the following chemical species is NOT amphoteric? a. H2O b. CO3–2 c. HPO4–2 d. NH3

b. CO3–2

All of the following statements are true EXCEPT a. Acids with high ionization constant have low pH b. Weak bases have low ionization constants c. Strong bases have high pH and ionization constants d. Weak acids have low pH and ionization constants

d. Weak acids have low pH and ionization constants Explanation: Weak acids do have low ionization constants (because they do not dissociate completely), but they typically have higher pH values compared to strong acids, not necessarily "low pH." Their pH tends to be between 4-6, which is higher than strong acids (which have very low pH values, often below 3). Other options: a. Acids with high ionization constant have low pH: True, because acids that ionize strongly (high ionization constant, Ka) release more H⁺ ions, leading to a lower pH. b. Weak bases have low ionization constants: True, weak bases do not ionize fully and therefore have low Kb (ionization constant). c. Strong bases have high pH and ionization constants: True, strong bases dissociate completely, leading to a high pH and a high Kb.

All of the following are concrete evidences of a chemical reaction EXCEPT a. change in color b. formation of precipitate c. evolution of gas d. evolution of heat

a. change in color Explanation: When we add red ink to water, it will turn red. However, we would indicate that as a physical change.

Which of the following concentration terms vary with temperature? a. mole fraction b. molarity c. molality d. none of these

b. molarity Molarity (moles of solute per liter of solution) can change with temperature because the volume of the solution can expand or contract with temperature changes.

Which of the following acid-base pairs will result in the formation of a buffer solution when titration is done before the equivalence point? a. NaOH and HCl b. KOH – HNO3 c. NH3 - HBr d. all of these

c. NH3 - HBr

In Mohr titration, which of the following statement is CORRECT? a. The indicator is usually kept at a concentration of 0.2-0.5 M so as not to obscure the red precipitate color b. At low pH, part of the indicator is present as HCrO4–1 and less Ag+ are required to reach the endpoint. c. At high pH, silver is precipitated as silver hydroxide thus produces error in the amount of titrant added. d. all of these

c. At high pH, silver is precipitated as silver hydroxide thus produces error in the amount of titrant added.

When performing calculations for standard additions, which of the following must be true? The volume of the standard added must be added with the volume of the sample used to give a new sample volume. The volume of the standard added is subtracted from the total volume of the sample used. The volume of the standard added can be ignored, because it is so small. The volume of the standard added can be ignored, because volumes are not used in the calculations. The volume of the standard added can be ignored, because it is part of the blank correction.

The volume of the standard added must be added with the volume of the sample used to give a new sample volume.

Which of the following statements about the sensitivity of an analytical method is true? The sensitivity of an analytical method is the same as its detection limit. The sensitivity of an analytical method is a measure of ability to determine whether slight differences in experimental results are significant. The sensitivity of an analytical method is the smallest amount of analyte that the instrument is able to measure. The sensitivity of an analytical method is the response of the instrument to human error. None of the above

The sensitivity of an analytical method is a measure of ability to determine whether slight differences in experimental results are significant.

Which of the following statements is true of the detection limit of an instrument? The detection limit of an instrument is the same as its sensitivity. The detection limit of an instrument is a measure of ability to determine whether slight differences in experimental results are significant. The detection limit of an instrument is the smallest amount of analyte that the instrument is able to measure. The detection limit of an instrument is the ability of the instrument to respond to an error. None of the above

The detection limit of an instrument is the smallest amount of analyte that the instrument is able to measure.

Fill in the blank. Precipitation, volatilization, and particulation are all types of ____________________. Electrochemical analysis methods Gravimetric analysis methods Tritrimetric analysis methods Spectroscopic analysis methods Photochemical analysis methods

Gravimetric analysis methods

Fill in the blank. Gravimetric analysis relies heavily on the principle of __________________. Conservation of energy Conservation of mass Constant compostition Definite proportions

Conservation of mass

Coprecipitates (inclusions, occlusions, and surface adsorbates) are a common problem in gravimetric analysis, but can be controlled by which of the following? Carefully controlling the solution conditions Reprecipitation of the solid Digestion of the precipitate Thoroughly washing and drying the filtrate All of the above

All of the above

Volatilization gravimetry would be most useful in determining which of the following? The amount of silver in a solution of silver nitrate The acidity of a water sample The amount of water in eposom salts All of the above None of the above

The amount of water in epsom salts

Which of the following statements about the equivalence point of an acid-base titration is true? The equivalence point of an acid-base titration is the same as the indicator endpoint. The equivalence point of an acid-base titration is the point where there is an equivalent amount of titrant and titrand. The equivalence point of an acid-base titration is where the pH = 7.0 (neutral). The equivalence point of an acid-base titration is where the entire volume of the burette has been used. The equivalence point of an acid-base titration is the average value of the dissociation constants.

The equivalence point of an acid-base titration is the point where there is an equivalent amount of titrant and titrand.

What is the stoichiometry of EDTA with metal ions? It is 1:6, because EDTA is a hexaprotic weak acid with six distinct acid dissociation values. It is 1:4, because EDTA has four binding sites upon loss of the four carboxylic acid protons. It is 1:2, because EDTA has two binding sites upon loss of the two ammonium protons. It is 1:1, because EDTA forms a cage-like structure around the metal ion. It is dependent on the metal ion present.

It is 1:1, because EDTA forms a cage-like structure around the metal ion.

Why must solutions with high concentrations be diluted prior to analysis via Beer's Law? The relationship between absorbance and concentration is not linear at high concentrations. The detector will reach its detection threshhold. The photon source is too weak to provide accurate results. The molar absorptivity of a compound is dependent on its concentration. There is no need to work with dilute concentrations; any concentration will work.

The relationship between absorbance and concentration is not linear at high concentrations.

Which of the following transitions is NOT possible in UV-Vis absorption? σ → σ* σ → n σ → π* n → π*

σ → π*

Which of the following typically exhibits the largest molar absorptivities? σ → σ* absorbances σ → n absorbances σ* → π* absorbances π → π* absorbances Metal to ligand charge transfer (MLCT) absorbances

Metal to ligand charge transfer (MLCT) absorbances MLCT transitions typically have very high molar absorptivities, often higher than other types of transitions because of the strong interaction between metal and ligand orbitals.

he method of continuous variations, also known as Job's method, uses the intersection of the ligand-line and the metal-line to determine which of the following? The concentration at which the detector can no longer respond to the signal The mole ratio between the metal and ligand in a complex The maximum intensity of source photons transmitted The number of dimeric molecules formed The oxidation number of the metal

The mole ratio between the metal and ligand in a complex

Ultraviolet and visible radiationaffect which of the following? Core electrons Valence electrons Nuclear spin Molecular vibrations Molecular rotations

Valence electrons

Infrared radiation affects which of the following? Core electrons Valence electrons Molecular vibrations Molecular rotations Nuclear spin

Molecular vibrations

Complete the sentence. All of the following are used to describe the bending modes in infrared spectroscopy, EXCEPT: In-plane rocking. In-plane scissoring. Assymetric stretching. Out-of-plane twisting. Out-of-plane wagging.

Asymmetric stretching. Asymmetric stretching: This is not a bending mode. Instead, it refers to the stretching of bonds where two atoms move in opposite directions, but along the bond axis. Stretching modes are different from bending modes.

What is the advantage of using a silver chloride sample cell rather than a sodium chloride sample cell for IR spectroscopy? Aquesous samples can be measured; AgCl is not water soluble. There is no advantage. Silver chloride does not absorb IR radiation. Silver chloride is translucent. Sodium chloride is less expensive.

Aqueous samples can be measured; AgCl is not water soluble. The advantage of using a silver chloride (AgCl) sample cell rather than a sodium chloride (NaCl) sample cell in IR spectroscopy primarily relates to their behavior in the presence of water. Key Differences: Sodium chloride (NaCl) is highly soluble in water, meaning that it dissolves easily if exposed to aqueous samples, which makes it unsuitable for measuring aqueous solutions. Silver chloride (AgCl), on the other hand, is not soluble in water, so it can be used for aqueous samples without the risk of the cell dissolving.

In order for a compound to be IR active, it must undergo which of the following? A change in polarizability A change in dipole moment Emission of an electron Transfer of an electon Metal-ligand charge transfer

A change in dipole moment

Complete the sentence. All of the following are infrared sources, EXCEPT: The Nernst glower. The Globar source. An incandescent wire. A pyroelectric glower.

A pyroelectric glower.

Complete the sentence. All of the following are detectors used in infrared spectroscopy, EXCEPT: A charge-coupled diode. A thermocouple. A pyroelectric detector. A photoelectric detector.

A charge-coupled diode. Charge-coupled diode (CCD): This is a detector typically used in visible light spectroscopy and imaging applications, but it is not commonly used in IR spectroscopy.

Fill in the blank. NMR affects a molecule's ________________. Nuclear spin Valence electrons Core electrons Molecular vibrations Molecular rotations

Nuclear spin

In 1H-NMR spectroscopy, if a CH2 neighbors a CH3, the hydrogen nuclei of the CH3 will appear as which of the following? A doublet, with a peak integration of 2 A doublet, with a peak integration of 3 A triplet, with a peak integration of 2 A triplet, with a peak integration of 3 A single peak, with an integration of 5

A triplet, with a peak integration of 3

The value of the chemical shift in NMR spectroscopy is directly related to which of the following? The amount of shielding The applied magnetic field The identity of the reference sample The electronegativity of the nucleus All of the above

All of the above

Chemical Formula of Diphosphorus monobromide

P2Br

This detects contamination from reagents, sample handling, and the entire measurement process. A. matched-matrix blank B. method blank C. solvent blank D. calibration blank

B. method blank

A water sample is collected for analysis of oil and grease. The analysis will not be done immediately. The sample should NOT be: A. collected in plastic bottle B. preserved with sulfuric acid C. refrigerated until analyzed D. collected in all glass bottle

A. collected in plastic bottle

The following statements are true about electrical conductivity EXCEPT: A. a measure of a solution's capacity to conduct electricity B. a measure of the total dissolved solids in a solution C. increasing temperature has no effect on its value D. conductivity is affected by temperature

C. increasing temperature has no effect on its value

A lab analyst dissolved 4.021 g of NaOH in water and made up the solution to 1 litre with water. He then pipetted 10.00 mL of this solution into a flask and titrated it with 0.050 M HCl 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 ________. A. the NaOH absorbed H2O from the air after its mass was measured B. the burette was rinsed with water instead of HCl 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 HCl

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. I only B. III only C. II and III only D. II only

A. I only At the equivalence point of a titration between a strong acid and a strong base (I), the resulting solution is neutral, resulting in a pH of 7.0.

What is the light source used in the visible range of 340-1000 nm? A. nerst blower B. tungsten C. deuterium D. incandescent

B. tungsten

81. For the reaction, Fe³⁺(aq) + SCN⁻(aq) ⇌ FeSCN²⁺(aq) The equilibrium constant for this reaction can best be determined by means of ______. A. Ion-exchange B. Conductance C. Spectrophotometry D. Chromatography

C. Spectrophotometry

Ammonia solution can be stored with the following chemicals EXCEPT for ______. A. cyclohexane solution B. acetic acid solution C. 2-propanol solution D. sodium hydroxide solution

B. acetic acid solution

What will you perform to know that the Atomic absorption spectrometer continues to work properly? A. Calibration check B. Blank C. QC sample recoveries D. Standard addition

A. Calibration check

The test that decides whether a datum from a given set could be rejected or NOT is A. T-test B. Z-test C. Q-test D. F-test

C. Q-test The Q-test is specifically designed to identify and reject outliers in a small data set. It compares the difference between the suspected outlier and the nearest value to the range of the data set. If the calculated Q value exceeds a critical value from the Q-test table, the datum can be rejected.

Using proper scientific notation, how would you round the number 9.9813 x 10-5 to two significant figures? A. 10. B. 9.9 x 10-5 C. 1.0 x 10-5 D. 1.0 x 10-6

D. 1.0 x 10-6

A chemist measured the mass of a wire using an analytical balance with the least count 0.001 g. The measured value should be recorded as: A. 5.3200 cm B. 5.3 cm C. 5.32 cm D. 5.320 cm

D. 5.320 cm

The type of biological Safety Levels which requires a separate building. A. BSL 1 B. BSL2 C. BSL 3 D. BSL 4

D. BSL 4

Which of the following is not a chemical-related health hazard? A. Carcinogenicity B. Reactivity C. Corrosivity D. Toxicity

B. Reactivity

17. If you transfer chemicals from a labeled container to a portable container, you don’t need to comply with standard hazardous material labeling requirements when: A. You hand the container off to someone else B. You leave the work area before using the materials C. You don’t use the materials before the end of your work shift D. None of the above

D. None of the above

Sections of the SDS regulated by OSHA A. 16 B. 12 C. 11 D. 4

A. 16

Section of the SDS that describes Hazard Identification A. Section 1 B. Section 2 C. Section 3 D. Section 4

B. Section 2

SDS Section which gives recommendations for the proper PPE A. Section 4 B. Section 6 C. Section 8 D. Section 10

C. Section 8

A document that lists information relating to occupational safety and health for the use of various substances and products. A. HMIS B. SDS C. HCP D. All

B. SDS A. HMIS (Hazardous Materials Identification System): A labeling system used to communicate hazards of chemicals but not a comprehensive document. B. SDS (Safety Data Sheet): A document that provides detailed information about the properties, hazards, handling, and safety precautions of various substances and products. It is specifically designed for occupational safety and health. C. HCP (Hazard Communication Program): A program that ensures communication of hazards but is not a document itself.

Arrange the given according to increasing ion size: Cation (C), Anion (A), Neutral Atom (N) A. C, A, N B. C, N, A C. N, C, A D. A, N, C

B. C, N, A Cations (C): These are positively charged ions formed when an atom loses one or more electrons. Cations are smaller than their neutral atoms because the loss of electrons reduces electron-electron repulsion and can pull the remaining electrons closer to the nucleus. Neutral Atoms (N): These are atoms that have not lost or gained electrons. Their size is larger than cations due to the presence of the same number of protons attracting more electrons. Anions (A): These are negatively charged ions formed when an atom gains one or more electrons. Anions are larger than their neutral atoms because the addition of electrons increases electron-electron repulsion, pushing the outer electrons farther from the nucleus.

The formula for hydrosulfuric acid is: A. H2S B. H2S(aq) C. H2SO3(aq) D. H2SO4(aq)

B. H2S(aq) Hydrosulfuric acid, also known as hydrogen sulfide

In the reaction, H2 + O2 → H2O, the limiting reactant is: A. H2 B. O2 C. H2O D. None

A. H2

The correct formula for Aluminum Bicarbonate is: A. Al2HCO3 B. Al2(HCO3)3 C. Al(HCO3)3 D. Al2(CO3)3

C. Al(HCO3)3

The formula for Iodic Acid is: A. HIO3(aq) B. HIO3 C. HIO4(aq) D. HIO4

A. HIO3(aq)

Can conduct electricity only at higher temperatures. They are: A. Metals B. Non-Metals C. Metalloids D. Conductors

C. Metalloids

56. Which of the following statements about acids and bases is not true: A. Water undergoes autoionization. B. Strong acids and strong bases are ionized completely in dilute aqueous solutions. C. The strength of an acid or a base is measured by the extent of its ionization in solution. D. Strong acids form strong conjugate bases.

D. Strong acids form strong conjugate bases.

Which statement about Arrhenius acids is FALSE? A. Their water solutions are called aqueous acids. B. They are molecular compounds with ionizable hydrogen atoms. C. Their pure aqueous solutions are electrolytes. D. They increase the concentration of hydroxide ions in aqueous solution.

D. They increase the concentration of hydroxide ions in aqueous solution.

58. Strong bases are: A. strong electrolytes. B. nonelectrolytes C. weak electrolytes D. also strong acids

A. strong electrolytes.

Systematic errors may arise from avoidable sources, except A. contamination, reagent impurities, B. wrongly calibrated instruments, instrumental mal- functions, C. poor sampling techniques, errors in calculations D. electronic noise in the circuit of an electrical instrument

D. electronic noise in the circuit of an electrical instrument

Systematic errors primarily influence a measurement's _________. A. Accuracy B. Precision C. Standard deviation D. Mean

A. Accuracy

An improperly calibrated thermometer may give accurate readings within a certain temperature range, but become inaccurate at higher or lower temperature. A. Random error B. Gross error C. Systematic error D. Analyst error

. Systematic error

An error caused by not setting an instrument to zero prior to its use is called an ______ error. A. Offset error B. Random error C. Gross error D. Systematic error

A. Offset error

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

D. All of the above

Primary sample preparation method for organics A. Sonication B. Acid-digestion C. Extraction D. All of the above

C. Extraction

Determinate errors, also called ____________. A. Bias B. Random error C. Gross error D. Systematic error

D. Systematic error A. Bias: While related, bias refers specifically to a consistent deviation from the true value, which is a type of systematic error. B. Random error: These are unpredictable and vary from one measurement to another, not consistent like determinate errors. C. Gross error: These are significant mistakes or blunders, which do not fall under the category of determinate errors. D. Systematic error: This is the correct term; determinate errors are also known as systematic errors because they consistently affect measurements in a predictable manner.

An error that is known to have occurred but was unavoidable A. Bias B. Random error C. Gross error D. Systematic error

B. Random error

Refers to the repeatability of a measurement. A. Accuracy B. Precision C. Specificity D. Mean

B. Precision

The holding time for samples for metal determination preserved using nitric acid, 4 mL of dilute 3:1 is A. 28 days B. 2 weeks C. 3 days D. 1 year

A. 28 days

The following are analytical strategy steps except for one. A. obtain the sample B. prepare the sample C. carry out the analysis method D. releasing of results

D. releasing of results Releasing of results is not typically considered an analytical strategy step, as it pertains more to the reporting phase after analysis, rather than the analytical process itself.

A student determines the weight of an object on an analytical balance to be 12.2843 g. The actual weight, unknown to the student or to anyone else, is 12.2845 g. What kind of error is this? A. Determinate B. indeterminate D. gross D. none of the above

B. indeterminate

A sample that has all the characteristics in exactly the same proportion as the bulk sample where it came from: A. representative sample B. test sample C. gross sample D. subsample

A. representative sample

In gravimetric analysis, A. the mass of a solution is used to calculate the quantity of the original analyte. B. the mass of a product is used to calculate the quantity of the original analyte. C. the mass of a product is used to calculate the quantity of the impurity. D. none of the above

B. the mass of a product is used to calculate the quantity of the original analyte.

Chemical derivatization is used to increase or decrease volatility for _________ analysis A. AAS B. GC and HPLC C. PCR D. X-ray Diffraction

B. GC and HPLC

GFAA (Graphite Furnace Atomic Absorption) do not use HCl since Cl- interferes. Diluted ______ acid is used. A. Phosphoric Acid B. Acetic acid C. Nitric Acid D. Sulfuric Acid

C. Nitric Acid

The original undivided sample that was taken directly from the bulk system being characterized. A. bulk sample B. test sample C. subsample D. laboratory sample

A. bulk sample

A primary sample is the same as A. Subsample B. test sample C. bulk sample D. laboratory sample

C. bulk sample

If a water sample is to be analyzed for trace levels of metals, glass container for sampling and storage is inappropriate due to the following reasons except for one. A. it could leach trace level metals and contaminate the sample B. it can absorb some analytes C. very impure as compared to quartz, PTFE, PP D. losses of elements due to adsorption are very high

B. it can absorb some analytes

An acid that turns paper towel black, a very dense syrupy liquid that gets especially hot when mixed with water is A. Sulfuric Acid B. Nitric Acid C. Hydrochloric Acid D. Perchloric Acid

A. Sulfuric Acid

PEL stands for A. personal exposure limit B. permissible exposure limit C. permissible exposure time length D. none of the above

B. permissible exposure limit

What does SPE stand for? A. Sample preparation evaluation B. Solid phase extraction C. Solid phase evaporation D. Sample processing experiment

B. Solid phase extraction

The label CORROSIVE on a chemical container indicates A. that the material is an oxidant B. that contact destroys living tissue as well as equipment C. that the material can degrade rapidly upon exposure to air D. All of the above

B. that contact destroys living tissue as well as equipment

When operating a fire extinguisher, remember the mnemonic PASS. PASS represents the steps used to properly operate the extinguisher and it stands for which of the following? A. Pin, Aim, See, Swing B Pull, Access, Seize, Sweep C. Plan, Access, Squeeze, Swing D. Pull, Aim, Squeeze, Sweep

D. Pull, Aim, Squeeze, Sweep

Given the unbalanced equation below, how many grams of carbon dioxide will be produced from one mole of glucose and six moles of oxygen? C6H12O6+O2→CO2+H2O A. 12 B. 4 C. 6 D.10

C. 6

A blank used to test the integrity of reagents used in the laboratory. For example, a new batch of solvent might be tested for impurities, or distilled or deionized water would be tested to ensure that it is pure. A. reagent blank B. field blank C. surrogate D. instrument blank

A. reagent blank

Which sampling term is incorrectly defined? A. laboratory sample – smaller, homogeneous sample taken from the bulk and has the same composition as the bulk B. lot – the total material from which samples are taken C. aliquot – small portions of the bulk sample taken for individual analysis D. sample preparation – the series of steps that convert a representative bulk sample into a form suitable for analysis

C. Aliquot: Incorrect. An aliquot refers to a measured, exact portion of a sample, not necessarily "small," but a specific, defined portion of a solution or sample used for analysis. It doesn't have to refer to the bulk sample directly, but rather to a portion of the prepared or diluted sample.

The liquid solution containing the analyte is passed through a cartridge containing a solid sorbent. A. Liquid-liquid extraction B. solid phase extraction C. purge-and-trap D. none of the above

B. solid phase extraction

The analyte in a sample may be too concentrated or too dilute for the chosen method. If it is too concentrated, a dilution with a compatible solvent may be performed. The dilution should be performed with _______________glassware and with good analytical technique so that the dilution factor is known and accuracy is not diminished. A. graduated glassware B. graduated plastic wares C. volumetric glassware D. nesslers tubes

C. volumetric glassware

Choose the sample that would be best dissolved by HNO3. A. NaCl B. Iron ore C. Copper metal D. Aluminum Oxide

The correct answer is C. Copper metal. Explanation: Nitric acid (HNO₃) is a strong oxidizing acid that reacts well with metals like copper (Cu) to form copper nitrate and nitrogen oxides. This reaction is commonly used to dissolve copper in analytical procedures. A. NaCl (sodium chloride): NaCl is an ionic salt, and while it can dissolve in water, it doesn't require HNO₃ for dissolution. B. Iron ore: This is a complex mixture that often contains oxides of iron and other elements. It may not dissolve effectively in HNO₃ alone, and other acids like hydrochloric acid (HCl) or a mixture like aqua regia (HNO₃ + HCl) would be more effective. D. Aluminum oxide: Aluminum oxide (Al₂O₃) is very resistant to chemical attack and requires stronger acids or specific conditions (such as fusion with sodium hydroxide) to dissolve. Nitric acid alone would not be effective. Thus, copper metal is best dissolved by HNO₃.

From the following list, choose those samples that would be best dissolved by HCl. A. NaCl B. Iron ore C. Gold metal D. Aluminum Oxide

B. Iron ore A. NaCl (Sodium Chloride): NaCl is already soluble in water, so it doesn't need HCl to dissolve. It dissolves easily in water without any need for acid. B. Iron ore: Iron ore typically contains iron oxides and other impurities. Hydrochloric acid (HCl) can effectively dissolve iron oxides by reacting to form iron(III) chloride, making it a suitable choice for dissolving iron-containing materials. C. Gold metal: Gold is a noble metal and is resistant to most acids, including HCl. Gold can only be dissolved using aqua regia (a mixture of HCl and HNO₃), not HCl alone. D. Aluminum Oxide (Al₂O₃): Aluminum oxide is highly resistant to HCl and would not dissolve well with hydrochloric acid alone. It requires stronger treatments such as alkaline solutions or fusion methods for dissolution.

HCl cannot be considered to be a primary standard because of its gaseous form at room temperature, but its solutions may be standardized against anhydrous ______. A. NaSO4 B. NaHCO3 C. Na2CO3 D. All of the above

C. Na2CO3

Blank samples are prepared so that you have a measure of the amount that needs always to be added to or subtracted from the end point to achieve the ________point. A. titration error B. equivalence C. accuracy D. precision

B. equivalence

A specially manufactured analytical reagent of exceptional purity for standardizing solutions and preparing reference standards. A. working standard B. secondary standard C. primary standard D. internal quality control standard

C. primary standard

A reagent that meets the standards of purity established by the manufacturer. The certificate of analysis is on the label. A. certified reagent B. secondary standard C. primary standard D. internal quality control standard

A. certified reagent

Chemicals of reasonable purity for applications that have no official standard for purity. A. Analyzed Reagent B. ACS grade C. Technical Grade D. Practical grade

C. Technical Grade

Solvents of suitable purity for use in spectrophotometric procedures. A certificate of analysis is on the label. A. Spectro grade B. HPLC grade C. Technical Grade D. Practical grade

A. Spectro grade

151. Chemicals of sufficiently high quality to be suitable for use in some syntheses. Organic chemicals of this grade may contain small amounts of intermediates, isomers, or homologs. A. USP or NF grade B. HPLC grade C. Technical Grade D. Practical grade

D. Practical grade

When an open bottle of _________________ sits next to an open bottle of ammonium hydroxide, thick white fumes form. A. Nitric acid B. Hydrochloric acid C. Sulfuric acid D. Hydroflouric acid

B. Hydrochloric acid When hydrochloric acid (HCl) is exposed to ammonia (from ammonium hydroxide, NH₄OH), it forms ammonium chloride (NH₄Cl), which appears as thick white fumes:

What acid is a highly corrosive mineral acid and is also known as aqua fortis (Latin for "strong water") and spirit of niter, is A. Nitric acid B. Hydrochloric acid C. Sulfuric acid D. Hydroflouric acid

A. Nitric acid

154. ____________________ diffuses through skin and is especially bad when it gets under the fingernails. A. Nitric acid B. Hydrochloric acid C. Sulfuric acid D. Hydroflouric acid

D. Hydroflouric acid Hydrofluoric acid (HF) is particularly dangerous because it can easily diffuse through the skin and is especially harmful when it gets under the fingernails. It can cause severe tissue damage and systemic toxicity, as it can penetrate tissues and bind with calcium in the body.

155. _____________________ is used to dissolve the sample for the Kjeldahl analysis. A. Nitric acid B. Hydrochloric acid C. Sulfuric acid D. Hydroflouric acid

C. Sulfuric acid Sulfuric acid (H₂SO₄) is commonly used in the Kjeldahl method to digest the sample and convert nitrogen-containing compounds into ammonium sulfate, which can then be quantified to determine the nitrogen content.

A mixture of concentrated HNO3 and HCl in the ratio of 1:3 HNO3:HCl is A. muriatic acid B. oil of vitriol C. aqua regia D. none of the above

C. aqua regia

If a given procedure calls for a pure methyl alcohol of the highest grade, then the ___________ should be used. A. ACS grade or AR grade B. Laboratory grade C. Technical grade D. USP grade

A. ACS grade or AR grade

The onset of a phase transition in a small region which can be the formation of a bubble or of a crystal from a liquid. A. Precipitation B. nucleation C. reprecipitation D. crystallization

B. nucleation

What type of balance uses an electromagnet to balance the object to be weighed on a single pan? A. macro balance B. electronic balance C. mechanical balance D. none of the above

B. electronic balance

A balance that is used to obtain four or five digits to the right of the decimal point in the analytical laboratory is called the (precision is ±0.1 or ±0.01 mg). A. macro balance B. electronic balance C. mechanical balance D. analytical balance

D. analytical balance

Refers to the process by which a balance is checked to see if the weight obtained for an object is correct. A. Validation B. verification C. calibration D. maintenance check

C. calibration

Gravimetric analysis methods proceed with the following steps: A.The weight or volume of the prepared sample is obtained, B. The analyte is either physically separated from the sample matrix or chemically altered and its derivative separated from the sample matrix C. The weight of the separated analyte or its derivative is obtained. D. All of the above

D. All of the above

This is an example of a loss through volatilization (evaporation) under temperature conditions at which water would volatilize. A. loss on drying B. loss on ignition C. loss on filtration D. none of the above

A. loss on drying

Ambient laboratory conditions are not the same to standard conditions, therefore the volumes dispensed in volumetric glassware are often not the same as the manufacturer's specifications, but within some acceptable limits determined by the manufacturer. This slight variation in volume will cause a _________ error that are based on volume-volume or mass- volume concentrations. A. Random B. systematic C. gross D. all of the above

B. systematic

Glass cuvettes are typically for use in the wavelength range of visible light, whereas fused quartz tends to be used for ____________ applications. A. Microwave B. IR C. uv/visible D. none of the above

C. uv/visible Fused quartz is commonly used for UV/visible applications because it has good transparency in the ultraviolet range and can withstand the wavelengths typically used in UV spectroscopy. Glass cuvettes, on the other hand, are generally limited to visible light applications due to their absorption in the UV range.

A stable light source in AAS analysis, which is necessary to emit the sharp characteristic spectrum of the element to be determined A. Tungsten lamp B. hollow cathode lamp C. deuterium lamp D. Nerst blower

B. hollow cathode lamp

Most popular burettes are 10 mL, 25 mL and 50 mL types. Which has the highest resolution? A. 25 mL B. 10 mL C. 50 mL D. All of the above

C. 50 mL

In verification of laboratory glassware, ________ is usually measured in terms of the tolerance, which is the uncertainty in a measurement made with the glassware. Class A volumetric glassware has a lower tolerance than Class B. A. Mean B. accuracy C. difference D. precision

B. accuracy

Total solids involve measuring a volume of the water or wastewater into a preweighed A. evaporating dish B. gooch crucible C. sintered crucible D. filter crucible

A. evaporating dish In the analysis of total solids, a volume of water or wastewater is typically placed in a preweighed evaporating dish. The sample is then evaporated to remove water, and the remaining solids are weighed to determine the total solids content.

Equipment that work by the sedimentation principle, where the centripetal acceleration is used to separate substances of greater and lesser density. A. Rotary evaporators B. Centrifuges C. Reciprocating shakers D. Rotary shakers

B. Centrifuges

Also known as droppers or eye droppers, are used to transfer small quantities of liquids. They are usually glass tubes tapered to a narrow point, and fitted with a rubber bulb at the top. A. Pasteur pipettes B. graduated pipettes C. capillary tubes D. Bulb pippetes

A. Pasteur pipettes

Small, cylindrical plastic containers with conical bottoms, typically with an integral snap cap. They are used in molecular biology and biochemistry to store and centrifuge small amounts of liquid. A. Eppendorf tubes B. capillary tubes C. microfuge tubes D. Falcon Tubes

C. microfuge tubes

A device used in chemical and biochemical laboratories for the efficient and gentle evaporation of solvents. The system works because lowering the pressure lowers the boiling point of liquids, including that of the solvent. A. Rotary evaporators B. Centrifuges C. Reciprocating shakers D. Rotary shakers

A. Rotary evaporators

All proteins absorb electromagnetic radiation of wavelength around 190 nm, which corresponds to a excitation in the protein molecule. In which region of the spectrum is this wavelength found? A. X-ray B. ultraviolet C. Visible D. Infrared

B. ultraviolet

The concentration at which the calibration curve departs from linearity by a specified amount. A. Limit of Blank B. Dynamic Range C. Limit of Linearity D. Limit of quantitation

C. Limit of Linearity

The highest apparent analyte concentration expected to be found when replicates of a blank sample containing no analyte are tested.. A. Limit of Detection B. Limit of Blank C. Limit of Linearity D. Limit of Quantitation

B. Limit of Blank

Conductivity could be determined using the distance between the electrodes and their surface area using Ohm's law but, for accuracy, a calibration is employed using _____ of well-known conductivity. A. acid solution B. basic solution C. electrolytes D. buffer solution

C. electrolytes Explanation: A. Acid solution: While acids can conduct electricity, they are not specifically used for calibrating conductivity meters. B. Basic solution: Similar to acids, basic solutions can conduct electricity but are not the standard for calibration. C. Electrolytes: These are substances that dissociate into ions in solution, allowing for electrical conductivity. Calibration with solutions of known conductivity (typically electrolyte solutions) ensures accuracy in measuring the conductivity of unknown samples. D. Buffer solution: Buffers maintain a specific pH but are not primarily used for conductivity calibration.

The electrical conductivity of water is directly related to the concentration of dissolved ionized solids in the water or A. Total Suspended Solids B. Total Dissolved Solids C. Volatile Solids D. Total Solids

B. Total Dissolved Solids

In complexometric titration, the most common used chelating agent is EDTA (ethylenediamine tetraacetic acid). EDTA's molecules will combine with metals to form chelate. EDTA is classified as a? A. Bidentate ligand B. Hexadentate ligand C. Tetradentate ligand D. Monodentate ligand

B. Hexadentate ligand

The property of a result of a measurement whereby it can be related to appropriate standards, generally national or international standards, through an unbroken chain of comparisons.” A. Calibration B. Accuracy C. Precision D. Traceability

D. Traceability

A method used to purify individual chemical compounds from mixtures of compounds. It is often used for preparative applications on scales from micrograms up to kilograms. A. column chromatography B. paper chromatography C. Flourescence spectrometry D. AAS

A. column chromatography

Used to purify sufficient quantities of a substance for further use, rather than analysis. A. analytical chromatography B. preparative chromatography C. size exclusion chromatography D. Ion chromatography

B. preparative chromatography

Size exclusion chromatography (SEC), is also known as ___________ which separates particles on the basis of size. It is generally a low resolution chromatography and thus it is often reserved for the final, "polishing" step of a purification, useful for determining the tertiary structure and quaternary structure of purified proteins. A. Reversed phase HPLC (RP-HPLC) B. Normal Phase HPLC C. Paper Chromatography D. Gel permeation chromatography or gel filtration chromatography

D. Gel permeation chromatography or gel filtration chromatography

A type of chromatography where the retention is based on the attraction between solute ions and charged sites bound to the stationary phase. Ions of the same charge are excluded. A. analytical chromatography B. preparative chromatography C. size exclusion chromatography D. Ion chromatography

D. Ion chromatography

The study of the interaction between radiation (electromagnetic radiation , or light, as well as particle radiation ) and matter . A. Spectrophotometry B. Spectrometry C. Spectrograph D. Spectroscopy

D. Spectroscopy

The basic operating principle of ________ is to force the analyte through a column of the stationary phase (usually a tube packed with small spherical particles with a certain surface chemistry) by pumping a liquid (mobile phase) at high pressure through the column. A. GC B. SEC C. Gel chromatography D. HPLC

D. HPLC

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