OrgChem-2019 Flashcards
1
Q
- Which of the following compounds has an Ionic bond?
I. H2O
II. NH4Cl
III. CH3Cl
IV. CH3Li
A. II
B. IV
C. I
D. III
A
A. II
1
Q
- How many hydrogen atoms are in one molecule of propene?
A. 4
B. 3
C. 6
D. 8
A
C. 6
2
Q
- In which species are all the carbon atoms considered to be sp2 hybridized?
l. C2H2
II. C2H4
Ill. C3H8
IV. C4H10
A. IV
B. Il
C. I
D. Ill
A
B. Il
3
Q
- For which compound are the empirical and molecular formulas the same?
I —- C6H5COOH
II —- C6H4(COOH)2
III —- HOOCCOOH
IV —- CH3COOH
A. Ill
B. I
C. IV
D. II
A
B. I
4
Q
- What Is the hybridization of the carbon atom in a carboxyl group?
A. sp
B. sp3
C. sp2
D. dsp3
A
C. sp2
4
Q
- How many different compounds have the formula C5H12?
A. 5
B. 2
C. 4
D. 3
A
D. 3
4
Q
- How many different alcohols have the molecular formula C4H10O?
A. 2
B. 4
C. 3
D. 5
A
B. 4
4
Q
- Which compound Is expected to be most soluble in water at 25oC
I —- N2 (g)
II —- O2 (g)
III —- (C2H5)2NH (l)
IV —- C2H5OC2H5 (l)
A. III
B. IV
C. I
D. II
A
A. III
4
Q
- In which species Is the carbon-nitrogen bond the shortest?
I. CH3NH2
II. CH2NH
Ill. (CH3)4N+
IV. CH3CN
A. Il
B. I
C. IV
D. Ill
A
C. IV
4
Q
- the gentle oxidation of ethanol (CH3CH2OH) produces ______
I — ethanal, CH3CHO
II — ethanoic acid,
III —carbon monoxide, CO
IV — carbon dioxide, CO2
A. IV
B. I
C. II
D. III
A
B. I
5
Q
- The following compounds have very similar molar masses. What would be the correct order when they
are arranged in order of increasing strength of their intermolecular forces.
l. C3H8
Il. CH3OCH3
III. CH3CH2OH
A. II < I < III
B. III < I < II
C. I < II < III
D. III < II < I
A
C. I < II < III
5
Q
- The process of heating a liquid mixture to form vapors and then cooling the vapors to get a pure
component is called
A. Distillation
B. Chromatography
C. Crystallization
D. Sublimation
A
A. Distillation
5
Q
- Which of the following hydrocarbon has the lowest boiling point?
l. C4H10
ll. CH4
Ill. C6H6
IV. C2H6
A. IV
B. II
C. I
D. III
A
B. II
5
Q
- In crystallization, the solution which is obtained after filtration is the
A. clear solution
B. colloidal solution
C. suspended solution
D. None of the given answers
A
A. clear solution
5
Q
- A reaction in which a carboxylic add reacts with an alcohol to form an organic compound and water Is
called
A. saponification
B. esterification
C. neutralization
D. hydrolysis
A
B. esterification
5
Q
- A constant boiling mixture of two in a solution is called a/an _______
A. azeotrope
B. Ideal
C. non-ideal solution
D. eutectic mixture
A
A. azeotrope
5
Q
- Which separation technique is based in the volatility of the compounds to be separated?
A. solvent extraction
B. distillation
C. paper chromatography
D. filtration
A
B. distillation
5
Q
- What is the position of the bromine atom relative to the methyl group in 3-bromotoluene?
A. meta
B. para
C. ortho
D. trans
A
A. meta
5
Q
- Which combination of reactants produces an ester?
A. aldehyde and potassium permanganate
B. acid and alcohol
C. acid and aldehyde
D. alcohol and aldehyde
A
B. acid and alcohol
5
Q
- Five grams an organic solid was dissolved in 100 mL of distilled water. Which of the following extraction
methods can remove the largest amount of organic solid from an aqueous solution?
A. Extract the aqueous solution with a 150-mL portion of ether.
B. Extract the aqueous solution with three 50-mL portions of ether.
C. Extract the aqueous solution with a 150-mL portion of acetic acid.
D. Extract the aqueous solution with three 50-mL portions of acetic acid.
A
B. Extract the aqueous solution with three 50-mL portions of ether.
5
Q
- Which class of compounds consist exclusively of saturated hydrocarbons?
A. alkenes
B. aromatics
C. alkynes
D. alkanes
A
D. alkanes
5
Q
- The smell of rancid butter is due to the presence of butyric (butanoic) acid. What is the for this
compound?
I — C4H8O2
II — C4H10O
III — C5H10O2
IV — C5H12O
A. IV
B. II
C. III
D. I
A
D. I
5
Q
- A common measure of efficiency in a fractionating column is the
A. length of the condenser used in the setup
B. number of distillation types
C. number of components in the solution
D. number of theoretical plates in the column
A
D. number of theoretical plates in the column
5
Q
- In crystallization, the crystal phases can be Inter-converted by varying ______
A. temperature
B. pressure
C. viscosity
D. size
A
A. temperature
5
Q
- Fractional distillation is different from distillation because of the presence of a _______
A. Fractionating column
B. Condenser
C. Conical flask
D. Distillation flask
A
A. Fractionating column
6
Q
- Which of the following is the example of crystallization process?
A. Purification of alum
B. None of the given answers
C. Separation of gases from air
D. Purification of sea water
A
A. Purification of alum
6
Q
- What is the key step in a recrystallization process?
A Taking the melting point of wet crystals
B. Dissolving the solid in a large quantity of cold solvent
C. Allowing the hot solution to cool slowly and let crystals grow
D. Removing the soluble impurities by vacuum filtration
A
C. Allowing the hot solution to cool slowly and let crystals grow
6
Q
- Which is the INCORRECT statement among the following?
A. An impure sample of the substance has a different melting point.
B. Two different pure substances have the same melting points.
C. Melting point serves as the criterion of purity of a solid substance.
D. Every pure crystalline substance has a characteristic and unique melting point.
A
B. Two different pure substances have the same melting points.
6
Q
- When the solid and liquid phases are in equilibrium, the temperature of the system
A. decreases gradually
B. none of the given answers
C. Increases gradually
D. remains constant
A
D. remains constant
6
Q
- Which of the following statements is correct?
A. Solid reactants can be weighed directly in the weighing pan of the analytical balance
B. Weight of liquids is approximately equal to its density.
C. Solid reactants can be transferred to a reaction flask by using a metal spatula.
D. Volatile liquids can be weighed by getting the mass of the empty vial with cap first.
A
D. Volatile liquids can be weighed by getting the mass of the empty vial with cap first.
6
Q
- Which of the following funnels should be used to filter hot mother liquor during recrystallization?
A. Buchner funnel
B. Hirsch funnel
C. Long stem funnel
D. Short stem funnel
A
D. Short stem funnel
6
Q
- A compound Is known to decompose at its boiling point. Which of the following can be to purity this
substance?
A. Steam distillation
B. Fractional distillation
C. Liquid-liquid extraction
D. Vacuum distillation
A
A. Steam distillation
6
Q
- The boiling point of a liquid is the temperature at which the vapor pressure is ______
A. lesser than internal pressure
B. equal to internal pressure
C. equal to external pressure
D. greater than internal pressure
A
C. equal to external pressure
7
Q
- A reaction mixture needs to be cooled to -77*C after refluxing. What Is the best method to be used?
A. Place the reaction vessel in an ice bath.
B. Place the reaction vessel in the freezer.
C. Place the reaction vessel in a salt and crushed ice mixture
D. Place tie reaction mixture in a dry ice-acetone mixture.
A
D. Place tie reaction mixture in a dry ice-acetone mixture.
7
Q
- Which of reactions will consume the most oxygen?
A. complete combustion one mole of octane
B. complete combustion of one mole of 2,3-dimethylhexane
C. complete combustion of one mole of 2,3,4-trimethylpentane
D. All the given compounds win consume the same amount of oxygen.
A
D. All the given compounds win consume the same amount of oxygen.
8
Q
- Which of the following techniques can be used to heat a reaction to 200*C?
A. Use a Bunsen burner to heat the reaction vessel.
B. use a heating mantle with stirring.
C. Place the reaction vessel in a sand bath with stirring.
D. Place the reaction vessel in a water bath with stirring.
A
C. Place the reaction vessel in a sand bath with stirring.
9
Q
- When proteins are broken down by enzymes, the products are ______
A. amino acids
B. fatty acids
C. nucleic acids
D. carbohydrates
A
A. amino acids
10
Q
- Which alkyl halide will most likely undergo SN2 mechanism?
A. 2-bromobutane
B. bromomethane
C. 2-bromo-2-methylpropane
D. 1-bromobutane
A
B. bromomethane
11
Q
- Aldehydes and ketones generally react by ______
A. nucleophilic substitution
B. nucleophilic addition
C. electrophile addition
D. electrophile substitution
A
B. nucleophilic addition
12
Q
- AICl3 is a catalyst used in the alkylation of aromatic compounds. It is a
A. a Lewis acid
B. a Lowry-Bronsted acid
C. an Arrhenius acid
D. a Lewis base
A
A. a Lewis acid
13
Q
- An Industrial source of alcohol is _______
A. Fats
B. Coal
C. Sugar
D. Ethers
A
C. Sugar
13
Q
- The chromaplate or thin layer chromatography plate is made up of
A. Wood
B. Fibro
C. Metal
D. Glass
A
D. Glass
14
Q
- The reaction rate is defined as the rate at concentration of the reactants ______ time or the rate at
which the concentration of products _______ with time
A. decrease, decrease
B. Increase, Increase
C. decrease, Increase
D. Increase. decrease
A
C. decrease, Increase
14
Q
- Hydrogenation of an alkene yields _______
A. alcohol
B. aldehyde
C. alkane
D. alkyne
A
C. alkane
14
Q
- The ion exchange resin with a functional group of HSO3- exchanges ions with _____
A. Small cations and anions
B. Cations
C. Large cations and anions
D. Anions
A
B. Cations
15
Q
- What of the following reactions are favored by polar aprotic solvent?
A. Both SN1 and SN2 reactions
B. SN1 reactions
C. None of the given choices
D. SN2 reactions
A
D. SN2 reactions
15
Q
- Benzene and its derivatives undergo substitution reactions instead of addition reactions because
A. the integrity of the benzene ring and the stable pi-bonding pattern remains intact
B. the benzene ring is sterically crowded, hence, substitution can occur
C. the hydrogens or benzene are relatively bound
D. the benzene is electron rich
A
A. the integrity of the benzene ring and the stable pi-bonding pattern remains intact
15
Q
- Quantitative analysis of compounds can be done using
A. Ion exchange chromatography
B. Liquid chromatography
C. Gas chromatography
D. Thin layer chromatography
A
C. Gas chromatography
15
Q
- A mobile phase can be classified as
I. Solid
II. Liquid
III. Gas
A. Il only
B. Ill
C. Il and Ill only
D. I only
A
C. Il and Ill only
15
Q
- Which of following Is produced when hydrogen is reacted with 2-butanone?
A. tertiary
B. aldehyde
C. primary alcohol
D. secondary alcohol
A
D. secondary alcohol
16
Q
- In thin layer chromatography, the solvent or mobile phase contained in a closed chamber is a mixture of
A. a liquid and a gas
B. liquid
C. solids
D. gases
A
B. liquid
17
Q
- Affinity chromatography Is used for the analysis and isolation of ______
A. All of the given answer
B. Insoluble starch substances
C. Enzyme tyrosinase
D. Antibodies bound with a covalently-attached antigen on cellulose column
A
A. All of the given answer
18
Q
- Retardation the ratio of
A. Distance moved by solvent from base line to distance moved by the substance from base line
B. Distance moved by substance from base line to distance moved by the solvent from base line
C. Distance moved by solvent from top fine to distance moved by the substance from top line
D. Distance moved by substance from top line to distance moved by the solvent from top line
A
B. Distance moved by substance from base line to distance moved by the solvent from base line
19
Q
- Gas-solid chromatography is ______ chromatography as basic principle Involved.
A. Absorption
B. Adsorption
C. Ion-exchange
D. Exclusion
A
B. Adsorption
19
Q
- Column chromatography is based on the principle of
A. Ion-exchange
B. Differential adsorption
C. Absorption
D. Exclusion principle
A
B. Differential adsorption
19
Q
- In thin layer chromatography, the relative adsorption of components of the mixture is expressed in
terms of its _______
A. Retardation factor
B. Solubility factor
C. Acceleration factor
D. Both acceleration end retardation factor
A
A. Retardation factor
20
Q
- In chromatography, the relative solubility of solute in both the phases determines the _____
A. Rate of disappearance of solute
B. Rate of movement of solvent
C. Rate of disappearance of solvent
D. Rate of movement of solute
A
D. Rate of movement of solute
20
Q
- The components of the in-column chromatography are eluted in order of
A. Increasing polarity end decreasing distribution ratio
B. Decreasing polarity and increasing distribution ratio
C. Increasing polarity and Increasing distribution ratio
D. Decreasing polarity and decreasing distribution ratio
A
C. Increasing polarity and Increasing distribution ratio
21
Q
- Which of the following chromatographic methods is most suitable for the analysis of high molecular
weight compounds that are soluble in non-polar solvents?
A. gas- liquid
B. gel filtration
C. ion-exchange
D. gel permeation
A
D. gel permeation
22
Q
- Which of the following is a NOT a characteristic of chromophores?
A. May contain extensive conjugated double bonds
B. Contains unsaturated functional group
C. Added to ions that do not strongly absorb light in the UV-visible region
D. Absorbs strongly at 800 nm
A
C. Added to ions that do not strongly absorb light in the UV-visible region
22
Q
- What the wavelength range for UV spectrum of light?
A. 400 nm - 700 nm
B. 10 nm to 400 nm
C. 700 nm to 1 mm
D. 0.01 nm to 10 nm
A
B. 10 nm to 400 nm
22
Q
- The elution power of a solvent is determined by
A. Its overall polarity
B. The polarity of the stationary phase
C. All of the given answers
D. The nature of the sample components
A
C. All of the given answers
22
Q
- Benzene has a smaller distribution ratio, D, In squalene than cyclohexane. squalene is an aliphatic type
of hydrocarbon. What is the order of elution of the two compounds from the GC column?
D = 𝑐𝑜𝑛𝑐𝑒𝑛𝑡𝑟𝑎𝑡𝑖𝑜𝑛 𝑜𝑓 𝑠𝑎𝑚𝑝𝑙𝑒 𝑖𝑛 𝑠𝑡𝑎𝑡𝑖𝑜𝑛𝑎𝑟𝑦 𝑝ℎ𝑎𝑠𝑒 /𝑐𝑜𝑛𝑐𝑒𝑛𝑡𝑟𝑎𝑡𝑖𝑜𝑛 𝑜𝑓 𝑠𝑎𝑚𝑝𝑙𝑒 𝑖𝑛 𝑚𝑜𝑏𝑖𝑙𝑒 𝑝ℎ𝑎𝑠e
A. Benzene will be eluted first
B. Cyclohexane will be eluted first.
C. The order of elution cannot be determined.
D. The two peaks will overlap.
A
A. Benzene will be eluted first
23
Q
- Alcohol and ether are often used as solvents. What Is the disadvantage of using these to dissolve
analytes for spectroscopic analysis in the UV-visible region?
A. They react with the analyte given the energy at this region.
B. Their solvents prevent the analyte from absorbing light.
C. They also absorb light at the UV-visible region.
D. They interfere in the transition of the electrons of the analyte
A
D. They interfere in the transition of the electrons of the analyte
23
Q
- Which is the correct statement from the following?
A. Molecular spectra is more complicated than atomic spectra
B. Molecular spectra arises from the transition of an electron between molecular energy levels
C. In molecular transitions. electronic, rotational and vibration transitions occurs
D. All of the given choices
A
D. All of the given choices
23
Q
- Which of the following Is an application of electronic spectroscopy?
A. Study of kinetics of chemical reaction
B. Control of purification
C. All of the given answers
D. Detection of impurities
A
C. All of the given answers
24
Q
- The different types of energies associated with a molecule are
A. Electronic energy
B. Rotational energy
C. All of the given answers
D. Vibrational energy
A
C. All of the given answers
25
Q
- Which of the following Is an application of molecular spectroscopy?
A. All of the given answers
B. Basis of understanding of colors
C. Structural investigation
D. Study of energetically excited reaction products
A
A. All of the given answers
25
Q
- Hazardous wastes by defining may be all of the following EXCEPT ______
A. Explosive
B. Toxic
C. Corrosive
D. Reactive
A
A. Explosive
25
Q
- formula of C7H14O exhibits an IR peak at 1715 cm-1. The compound may be a/an ____
A. ketone
B. ether
C. ester
D. alcohol
A
A. ketone
25
Q
- At which region can be found the peaks due to N — H, C — H and O — H stretching and bending
motions?
A. 2500 to 2000 cm-1
B. 1500 to 1000 cm-1
C. 4000 to 2500 cm-1
D. 2000 to 1500 cm-1
A
C. 4000 to 2500 cm-1
26
Q
- Which treatment method is NOT typically used to remove organic compounds?
A. Thermal
B. Biological
C. Physical
D. Chemical
A
A. Thermal
26
Q
- Which treatment of wastes can be done in situ?
A. Air stripping
B. Chemical degradation
C. All of the given answers
D. Biodegradation
A
C. All of the given answers
26
Q
- Waste solvents which are halogenated should be placed in separate containers from non-halogenated
waste solvents because ______.
A. Non-halogenated waste solvents are more toxic.
B. They are not compatible with each other.
C. They will react with each other.
D. The cost to properly dispose halogenated waste solvents is higher
A
D. The cost to properly dispose halogenated waste solvents is higher
27
Q
- The following are requirements for hazardous waste storage EXCEPT
A. The floors should be impermeable liquids and resistant to attack by chemicals.
B. Drums should be preferably stored upright or pallets and stacked no more than four drums
C. The facility should be enclosed but ventilated.
D. The facility should be properly secured and can be easily accessed by anyone.
A
D. The facility should be properly secured and can be easily accessed by anyone.
27
Q
- All of the following about hazardous waste containers are true, EXCEPT for the following
A. Containers must be closed except when removing or adding waste.
B. Any type of container, Including food containers. can be used to contain hazardous waste.
C. Contents must be compatible with the type of waste containers.
D. Containers must be clean on the outside.
A
B. Any type of container, Including food containers. can be used to contain hazardous waste.
28
Q
- Which is the correct procedure for mixing acid and water?
A. Pour acid into water
B. Pour them at the same time
C. Pour water into acid
D. Let the supervisor pour them
A
A. Pour acid into water
28
Q
- Which of the following is an acceptable practice when working in a chemical laboratory?
A. Wearing a laboratory coat and safety goggles while performing the analysis
B. Wearing sandals or open-toed shoes
C. Eating and drinking inside the chemical laboratory
D. Wearing gloves to touch door handles, elevator buttons, etc.
A
A. Wearing a laboratory coat and safety goggles while performing the analysis
28
Q
- Segregation of waste organic solvents is very important because _______
A The costs for disposal of waste solvents differ.
B. Some waste solvents can still be recycled.
C. Waste solvents differ in proper treatment.
D: All of the given answers
A
D: All of the given answers
28
Q
- How is clean, unbroken or broken glass waste to be disposed of?
A. Into a cardboard box lined with a black bag and taped. For small quantities of broken glass. put into
sharps container
B. Into containers lined with black bags
C. Into containers lined with yellow bags.
D. Into containers lined with clear bags
A
A. Into a cardboard box lined with a black bag and taped. For small quantities of broken glass. put into
sharps container
28
Q
- Which method is considered an unacceptable means of disposing waste?
A. All methods given are unacceptable
B. Pouring down the sink
C. Placing in the regular trash
D. Pouring down the drainage canal
A
A. All methods given are unacceptable
28
Q
- Which of the following colors used on the ‘NFPA diamond” chemical hazard warning label represents
the health hazard?
A. Red
B. Blue
C. Yellow
D. White
A
B. Blue
28
Q
- Which of the following pair is not correct about NFPA diamond chemical label hazard warning?
A. Blue: 0 highly toxic
B. Blue: health
C. Red: flammability
D. Red: 0 non-flammable
A
A. Blue: 0 highly toxic
29
Q
- If you discover that a hazardous waste container has a minor leak. what should you do?
A. Patch the leaking hazardous waste container.
B. Place the leaking container on to a secondary container so that the waste will be property collected until
It is removed from the laboratory.
C. Immediately transfer the hazardous waste to another empty container in good condition.
D. Immediately notify the Pollution Control Officer so that an environmental report may be filed with the
regulatory agency.
A
C. Immediately transfer the hazardous waste to another empty container in good condition.
29
Q
- When a chemical splashes In the eye, rinse for ______
A. 10 seconds
B. 30 seconds
C. 5 minutes
D. 15 minutes
A
D. 15 minutes
29
Q
- The sign shown below Indicates what type of safety hazard?
A. Chemical — hazardous liquids; danger to skin and other materials
B. Flammable — possible burn hazard; use caution
C. Toxic — poisonous if touched, swallowed, or inhaled
D. Radioactivity — radioactive materials; use caution
A
B. Flammable — possible burn hazard; use caution
29
Q
- Which of the sign shown below Indicates warning about corrosive chemicals?
A. II
B. IV
C. I
D. Ill
A
C. I
30
Q
- What type of safety hazard is indicated by the sign shown below.
A. Toxic — poisonous if touched, swallowed, or inhaled
B. Biological — harmful to humans.
C. Radioactivity — radioactive materials: use caution
D. Chemical — hazardous liquids; danger to skin and Other materials
A
C. Radioactivity — radioactive materials: use caution
31
Q
- Flammable liquids burn only when their vapor is mixed with air in the appropriate concentration. When
handling flammable liquids, you should _______
A avoid nearby sources of ignition
B. use adequately ventilated work areas
C. keep containers closed except during transfer of Contents
D. minimize the creation of flammable vapors
A
D. minimize the creation of flammable vapors
32
Q
- Organic peroxides are particularly dangerous when ________
A. concentrated
B. all of the above
C. when ethyl ether or tetrahydrofuran is left open to the air md allowed to evaporate
D. heated
A
B. all of the above
