DP Chemistry Questionbank

Which alcohols are oxidized by acidified potassium dichromate(VI) solution when heated?

A. I and II only 

B. I and III only 

C. II and III only 

D. I, II and III

The structures of two molecules, X and Y, are shown below.

(i) Justify why both these molecules are carbohydrates.

(ii) Distinguish between these molecules in terms of their functional groups.

Compare and contrast the functional groups present in methadone and diamorphine (heroin), giving their names. Use section 37 of the data booklet.

What are the functional groups in the aspirin molecule?

A.     I and II only

B.     I and III only

C.     II and III only

D.     I, II and III

Which molecule has a tertiary nitrogen?

A.     (CH₃)₂NH

B.     (C₂H₅)₄N⁺I⁻

C.     C₃H₇N(CH₃)₂

D.     C₆H₅NH₂

Ethane, C₂H₆, reacts with chlorine in sunlight. State the type of this reaction and the name of the mechanism by which it occurs.

One possible product, X, of the reaction of ethane with chlorine has the following composition by mass:

carbon: 24.27%, hydrogen: 4.08%, chlorine: 71.65%

Determine the empirical formula of the product.

The mass and ¹H$$NMR spectra of product X are shown below. Deduce, giving your reasons, its structural formula and hence the name of the compound.

Chloroethene, C₂H₃Cl, can undergo polymerization. Draw a section of the polymer with three repeating units.

Discuss the physical evidence for the structure of benzene.

State the typical reactions that benzene and cyclohexene undergo with bromine.

One possible product, X, of the reaction of ethane with chlorine has the following composition by mass:

carbon: 24.27%, hydrogen: 4.08%, chlorine: 71.65%

Determine the empirical formula of the product.

The mass and ¹H NMR spectra of product X are shown below. Deduce, giving your reasons, its structural formula and hence the name of the compound.

State the reagents used to convert benzene to nitrobenzene and the formula of the electrophile formed.

Describe the difference in their structures.

Explain why the difference in their structures affects their melting points.

Deduce the formula of the biodiesel formed when the vegetable oil shown is reacted with the reagents in (a).

Which compound contains a secondary carbon atom?

A.     CH₃CH(Cl)CH(CH₃)₂

B.     (CH₃)₂CHCH₂Cl

C.     (CH₃)₃CCl

D.     CH₃CH₂Cl

In which order should the reagents be used to convert benzene into phenylamine (aniline)?

Using relevant equations, show the initiation and the propagation steps for this reaction.

Bromine was added to hexane, hex-1-ene and benzene. Identify the compound(s) which will react with bromine in a well-lit laboratory.

Identify one organic functional group that can react with acidified K₂Cr₂O₇(aq).

The overall equation for monochlorination of methane is:

CH₄(g) + Cl₂(g) → CH₃Cl(g) + HCl(g)

Calculate the standard enthalpy change for the reaction, ΔH ^θ, using section 12 of the data booklet.

Identify the functional group that shows stretching at 1710 cm^–1 in the infrared spectrum of this compound using section 26 of the data booklet and the ¹H NMR.

Suggest the structural formula of this compound.

Bromine was added to hexane, hex-1-ene and benzene. Identify the compound(s) which will react with bromine in a well-lit laboratory.

State the reagents and the name of the mechanism for the nitration of benzene.

Hydrogenation of propene produces propane. Calculate the standard entropy change, ΔS^θ, for the hydrogenation of propene.

Identify the functional groups which are present in only one structure of glucose.

Subsequent steps proceed under differing conditions, forming the dendrimer polymer with the following repeating unit.

State the name of one functional group in this repeating unit.

Suggest two absorbances, other than the absorbances due to the ring structure and C–H bonds, that would be present in the infrared (IR) spectrum of aspirin.

One possible Lewis structure for benzene is shown.

State one piece of physical evidence that this structure is incorrect.

Deduce the name of the class of compound formed when the product of (c)(i) reacts with butanoic acid.

Deduce the structural formulas of the two possible isomers.

One possible Lewis structure for benzene is shown.

State one piece of physical evidence that this structure is incorrect.

The Kekulé structure of benzene suggests it should readily undergo addition reactions.

Discuss two pieces of evidence, one physical and one chemical, which suggest this is not the structure of benzene.

Describe two differences, other than the number of atoms, between the models of ethane and ethene constructed from the kit shown.

The above ball and stick model is a substituted pyridine molecule (made of carbon, hydrogen, nitrogen, bromine and chlorine atoms). All atoms are shown and represented according to their relative atomic size.

Label each ball in the diagram, excluding hydrogens, as a carbon, C, nitrogen, N, bromine, Br, or chlorine, Cl.

Pyridine, like benzene, is an aromatic compound.

Outline what is meant by an aromatic compound.

What is the order of increasing boiling point for the isomers of C₅H₁₂?

A.   CH₃CH₂CH₂CH₂CH₃ < CH₃CH(CH₃)CH₂CH₃ < CH₃C(CH₃)₃

B.   CH₃C(CH₃)₃ < CH₃CH(CH₃)CH₂CH₃ < CH₃CH₂CH₂CH₂CH₃

C.   CH₃C(CH₃)₃ < CH₃CH₂CH₂CH₂CH₃ < CH₃CH(CH₃)CH₂CH₃

D.   CH₃CH(CH₃)CH₂CH₃ < CH₃C(CH₃)₃ < CH₃CH₂CH₂CH₂CH₃

Draw the structural formula of propan-2-ol.

The compound could not be oxidized using acidifi ed potassium dichromate(VI).

Deduce the structural formula of the compound.

Draw two structural isomers of methyloxirane.

Draw the structure of one other isomer of xylene which retains the benzene ring.

Outline one piece of physical evidence for the structure of the benzene ring.

Determine the enthalpy change for the reaction, in kJ, to produce A using section 11 of the data booklet.

Which compound has the lowest boiling point?

A. CH₃CH₂CH₂CH₂CH₂CH₃

B. CH₃CH₂CH₂CH₂CH₃

C. CH₃CH(CH₃)CH₂CH₃

D. CH₃C(CH₃)₂CH₃

Draw the structure of one other isomer of xylene which retains the benzene ring.

State the name of product B, applying IUPAC rules.

State the name of the functional group which allows the molecule to be responsive to applied electric fields.

Which compound has the lowest boiling point?

A. CH₃CH₂CH₂CH₂CH₂CH₃

B. CH₃CH₂CH₂CH₂CH₃

C. CH₃CH(CH₃)CH₂CH₃

D. CH₃C(CH₃)₂CH₃

Explain why the compound C₃H₈O, produced in (a)(iv), has a higher boiling point than compound C₃H₆O, produced in d(i).

Explain why the ¹H NMR spectrum of C₃H₆O, produced in (d)(i), shows only one signal.

Draw the structure of the dipeptide Asp–Phe using section 33 of the data booklet.

Infrared (IR) spectroscopy is used to identify functional groups in organic compounds.

Deduce the wavenumber, in cm⁻¹, of an absorption peak found in the IR spectrum of testosterone but not in that of cholesterol.

Describe a technique for the detection of steroids in blood and urine.

Explain how redox chemistry is used to measure the ethanol concentration in a breathalyser.

Explain why the compound C₂H₆O, produced in (b), has a higher boiling point than compound C₂H₄O, produced in d(i).

Draw the structure of the dipeptide Asp–Phe using section 33 of the data booklet.

Which compound with the molecular formula ${\mathrm{C}}_4{\mathrm{H}}_8\mathrm{O}$ has this high resolution ${}_1\mathrm{H} \mathrm{NMR}$?

From: libretexts.org. Courtesy of Chris Schaller, Professor (Chemistry)
at College of Saint Benedict/Saint John’s University.

A.  but-3-en-2-ol, ${\mathrm{CH}}_2=\mathrm{CHCH}\left(\mathrm{OH}\right){\mathrm{CH}}_3$

B.  butanal, ${\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{CH}}_2\mathrm{CHO}$

C.  butanone, ${\mathrm{CH}}_3{\mathrm{COCH}}_2{\mathrm{CH}}_3$

D.  but-3-en-1-ol, ${\mathrm{CH}}_2={\mathrm{CHCH}}_2{\mathrm{CH}}_2\mathrm{OH}$

Ethoxyethane (diethyl ether) can be used as a solvent for this conversion. Draw the structural formula of ethoxyethane

The IR spectrum of one of the compounds is shown:

COBLENTZ SOCIETY. Collection © 2018 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

Deduce, giving a reason, the compound producing this spectrum.

Compound A and B are isomers. Draw two other structural isomers with the formula ${\mathrm{C}}_3{\mathrm{H}}_6\mathrm{O}$.

Ethoxyethane (diethyl ether) can be used as a solvent for this conversion.
Draw the structural formula of ethoxyethane

The IR spectrum of one of the compounds is shown:

COBLENTZ SOCIETY. Collection © 2018 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

Deduce, giving a reason, the compound producing this spectrum.

Compound A and B are isomers. Draw two other structural isomers with the formula ${\mathrm{C}}_3{\mathrm{H}}_6\mathrm{O}$.

Suggest a wavenumber absorbed by methane gas.

Suggest a wavenumber absorbed by methane gas.

Which spectra would show the difference between propan-2-ol, CH₃CH(OH)CH₃, and propanal, CH₃CH₂CHO?

I.   mass
II.  infrared
III. ¹H NMR

A.  I and II only

B.  I and III only

C.  II and III only

D.  I, II and III

Write the equation and name the organic product when ethanol reacts with methanoic acid.

Which is a homologous series?

A.  C₂H₄, C₃H₅, C₄H₆

B.  C₂H₂, C₃H₄, C₄H₆

C.  C₂H₂, C₂H₄, C₂H₆

D.  C₂H₂, C₄H₄, C₆H₆

State the name of Compound A, applying International Union of Pure and Applied Chemistry (IUPAC) rules.

State the name of Compound B, applying International Union of Pure and Applied Chemistry (IUPAC) rules.

Suggest two differences in the ¹H NMR of but-2-ene and the organic product from (d)(ii).

Suggest two differences in the ¹H NMR of but-2-ene and the organic product from (d)(ii).

Deduce the splitting pattern in the ¹H NMR spectrum for 1-bromopropane.

Which monomer is used to form the polymer with the following repeating unit?

A. CH₃CH=CHCH₃ 

B. CH₃CH₂CH=CH₂ 

C. CH₃CH₂CH₂CH₃ 

D. (CH₃)₂C=CH₂

Ethane-1,2-diol can be oxidized first to ethanedioic acid, (COOH)₂, and then to carbon dioxide and water. Suggest the reagents to oxidize ethane-1,2-diol.

Both propane and propene react with bromine.

(i) State an equation and the condition required for the reaction of 1 mol of propane with 1 mol of bromine.

(ii) State an equation for the reaction of 1 mol of propene with 1 mol of bromine.

(iii) State the type of each reaction with bromine.

Propane:

Propene:

Ethane, C₂H₆, reacts with chlorine in sunlight. State the type of this reaction and the name of the mechanism by which it occurs.

Formulate equations for the two propagation steps and one termination step in the formation of chloroethane from ethane.

Chloroethene, C₂H₃Cl, can undergo polymerization. Draw a section of the polymer with three repeating units.

Discuss the physical evidence for the structure of benzene.

State the typical reactions that benzene and cyclohexene undergo with bromine.

Deduce the repeating unit of the polymer and the other product of the reaction.

Using relevant equations, show the initiation and the propagation steps for this reaction.

Bromine was added to hexane, hex-1-ene and benzene. Identify the compound(s) which will react with bromine in a well-lit laboratory.

Polyvinyl chloride (PVC) is a polymer with the following structure.

State the structural formula for the monomer of PVC.

Identify one organic functional group that can react with acidified K₂Cr₂O₇(aq).

The overall equation for monochlorination of methane is:

CH₄(g) + Cl₂(g) → CH₃Cl(g) + HCl(g)

Calculate the standard enthalpy change for the reaction, ΔH ^θ, using section 12 of the data booklet.

Bromine was added to hexane, hex-1-ene and benzene. Identify the compound(s) which will react with bromine in a well-lit laboratory.

Deduce the structural formula of the main organic product when hex-1-ene reacts with hydrogen bromide.

Suggest, giving one reason, whether this is an addition or condensation reaction.

Which compound can be oxidized when heated with an acidified solution of potassium dichromate(VI)?

A. CH₃C(O)CH₂CH₃

B. CH₃CH₂CH(OH)CH₃

C. (CH₃)₃COH

D. CH₃(CH₂)₂COOH

Deduce the type of chemical reaction and the reagents used to distinguish between these compounds.

State the observation expected for each reaction giving your reasons.

Explain, with the help of equations, the mechanism of the free-radical substitution reaction of ethane with bromine in presence of sunlight.

Ethyne, like ethene, undergoes hydrogenation to form ethane. State the conditions required.

Outline the formation of polyethene from ethene by drawing three repeating units of the polymer.

Ethyne reacts with chlorine in a similar way to ethene. Formulate equations for the following reactions.

State the organic product of the reaction between 1-chlorobutane, CH₃CH₂CH₂CH₂Cl, and aqueous sodium hydroxide.

Which compound could be formed when CH₃CH₂CH₂OH is heated with acidified potassium dichromate(VI)?

        I.     CH₃CH₂CHO

        II.     CH₃CH₂COOH

        III.     CH₃COCH₃

A.     I and II only

B.     I and III only

C.     II and III only

D.     I, II and III

Ethyne, like ethene, undergoes hydrogenation to form ethane. State the conditions required.

Outline the formation of polyethene from ethene by drawing three repeating units of the polymer.

State the characteristic reaction mechanism of benzene.

Formulate the ionic equation for the oxidation of propan-1-ol to the corresponding aldehyde by acidified dichromate(VI) ions. Use section 24 of the data booklet.

The aldehyde can be further oxidized to a carboxylic acid.

Outline how the experimental procedures differ for the synthesis of the aldehyde and the carboxylic acid.

Which compounds cause the colour of acidified potassium manganate(VII) solution to change from purple to colourless?

I.    CH₃CH₂CH₂CH₂OH

II.   (CH₃)₃CCH₂OH

III.  CH₃CH₂CH(OH)CH₃

A.   I and II only

B.   I and III only

C.   II and III only

D.   I, II and III

Which compounds react to form CH₃CH₂CH₂COOCH(CH₃)₂?

A.   propanoic acid and propan-2-ol

B.   propanoic acid and butan-2-ol

C.   butanoic acid and propan-1-ol

D.   butanoic acid and propan-2-ol

State a suitable oxidizing agent for the oxidation of propan-2-ol in an acidified aqueous solution.

Deduce the product of the oxidation of propan-2-ol with the oxidizing agent in (d)(i).

Identify the initiation step of the reaction and its conditions.

1,4-dimethylbenzene reacts as a substituted alkane. Draw the structures of the two products of the overall reaction when one molecule of bromine reacts with one molecule of 1,4-dimethylbenzene.

Formulate the equation for the complete combustion of benzoic acid in oxygen using only integer coefficients.

Write an equation for the complete combustion of ethyne.

State the name of product B, applying IUPAC rules.

Suggest the reagents and conditions required to ensure a good yield of product B.

Reagents: 

Conditions:

Draw the repeating unit of polyphenylethene.

Which alcohol would produce a carboxylic acid when heated with acidified potassium dichromate(VI)?

A. propan-2-ol

B. butan-1-ol

C. 2-methylpropan-2-ol

D. pentan-3-ol

Methane reacts with chlorine in sunlight.

CH₄ (g) + Cl₂ (g) → CH₃Cl (g) + HCl (g)

Which type of reaction occurs?

A. free-radical substitution

B. electrophilic substitution

C. nucleophilic substitution

D. electrophilic addition

What must be present on a nucleophile?

A. Negative charge

B. Lone pair of electrons

C. Positive charge

D. Symmetrical distribution of electrons

Identify the initiation step of the reaction and its conditions.

1,4-dimethylbenzene reacts as a substituted alkane. Draw the structures of the two products of the overall reaction when one molecule of bromine reacts with one molecule of 1,4-dimethylbenzene.

Formulate the equation for the complete combustion of benzoic acid in oxygen using only integer coefficients.

Write an equation for the complete combustion of ethyne.

Product A contains a carbon–carbon double bond. State the type of reactions that compounds containing this bond are likely to undergo.

Which alcohol would produce a carboxylic acid when heated with acidified potassium dichromate(VI)?

A. propan-2-ol

B. butan-1-ol

C. 2-methylpropan-2-ol

D. pentan-3-ol

Methane reacts with chlorine in sunlight.

CH₄ (g) + Cl₂ (g) → CH₃Cl (g) + HCl (g)

Which type of reaction occurs?

A. free-radical substitution

B. electrophilic substitution

C. nucleophilic substitution

D. electrophilic addition

Write an equation for the complete combustion of the compound C₃H₈O formed in (a)(iv).

State the reagents for the conversion of the compound C₃H₈O formed in (a)(iv) into C₃H₆O.

Draw the structure of the monomers of Kevlar^® if the by-product of the condensation polymerization is hydrogen chloride.

Write the equation for the complete combustion of ethanol.

Explain how redox chemistry is used to measure the ethanol concentration in a breathalyser.

Write an equation for the reaction of C₂H₅Cl with aqueous sodium hydroxide to produce a C₂H₆O compound, showing structural formulas.

Write an equation for the complete combustion of the organic product in (b).

State the reagents and conditions for the conversion of the compound C₂H₆O, produced in (b), into C₂H₄O.

Which molecule can be oxidized to a carboxylic acid by acidified potassium dichromate(VI)?

A.  Propan-1-ol

B.  Propan-2-ol

C.  2-methylpropan-2-ol

D.  Propanone

State the type of reaction occurring when ethane reacts with chlorine to produce chloroethane.

Predict, giving a reason, whether ethane or chloroethane is more reactive.

Write the equation for the reaction of chloroethane with a dilute aqueous solution of sodium hydroxide.

Deduce the nucleophile for the reaction in d(iii).

State the type of reaction occurring when ethane reacts with chlorine to produce chloroethane.

Predict, giving a reason, whether ethane or chloroethane is more reactive.

Which monomer would produce the polymer shown?

A.  ${\text{CF}}_{\text{3}}{\text{CCl}}_{\text{2}}\text{F}$

B.  ${\text{CF}}_{\text{3}}\text{CClHF}$

C.  ${\text{CF}}_{\text{2}}\text{CClF}$

D.  ${\text{CF}}_{\text{2}}{\text{CF}}_{\text{2}}$

Which monomer forms the polymer shown?

A.  ${\text{CH(Cl)=CH(CH}}_{\text{3}}\text{)}$

B.  ${\text{CH}}_{\text{2}}{\text{=C(Cl)CH}}_{\text{3}}$

C.  ${\text{(CH}}_{\text{3}}{\text{)}}_{\text{2}}\text{CHCl}$

D.  ${\text{CH}}_{\text{2}}\text{=CHCl}$

Which is a propagation step in the free-radical substitution mechanism of ethane with chlorine?

A.  C$\text{l}$₂ → 2 •C$\text{l}$

B.  •C₂H₅ + C$\text{l}$₂ → C₂H₅C$\text{l}$ + •C$\text{l}$

C.  •C₂H₅ + •C$\text{l}$ → C₂H₅C$\text{l}$

D.  C₂H₆ + •C$\text{l}$ → C₂H₅C$\text{l}$ + •H

Which can be reduced to a secondary alcohol?

A.  C₂H₅COOH

B.  CH₃CH₂OCH₃

C.  (CH₃)₂CHCHO

D.  CH₃COC₂H₅

Several compounds can be synthesized from but-2-ene. Draw the structure of the final product for each of the following chemical reactions.

Oxidation of ethanol with potassium dichromate, K₂Cr₂O₇, can form two different organic products. Determine the names of the organic products and the methods used to isolate them.

Several compounds can be synthesized from but-2-ene. Draw the structure of the final product for each of the following chemical reactions.

Oxidation of ethanol with potassium dichromate, K₂Cr₂O₇, can form two different organic products. Determine the names of the organic products and the methods used to isolate them.

Write the equation and name the organic product when ethanol reacts with methanoic acid.

Which reagents and conditions are best for converting propan-1-ol into propanoic acid?

A.  Reflux with acidified potassium dichromate (VI)

B.  Reflux with aqueous sodium hydroxide

C.  Distil with acidified potassium dichromate (VI)

D.  Distil with aqueous sodium hydroxide

Which reagents and conditions are best for converting propan-1-ol into propanoic acid?

A.  Reflux with acidified potassium dichromate (VI)

B.  Reflux with LiAlH₄

C.  Distil with acidified potassium dichromate (VI)

D.  Distil with LiAlH₄

Which combination best describes what is happening to chloromethane, CH₃Cl, in the equation below?

CH₃Cl (g) + H₂(g) $\rightleftharpoons$ CH₄(g) + HCl (g)

A.  Oxidation and addition

B.  Oxidation and substitution

C.  Reduction and addition

D.  Reduction and substitution

Which structure represents a repeating unit of a polymer formed from propene?

A.  –CH₂–CH(CH₃)–

B.  –CH₂–CH₂–CH₂–

C.  –CH(CH₃)–CH(CH₃)–

D.  –CH₂–CH₂–

Which reaction involves homolytic fission?

A.  CH₄ + Cl₂

B.  CH₃Br + NaOH

C.  (CH₃)₃CBr + NaOH

D.  C₆H₆ + HNO₃ + H₂SO₄

Deduce what would be observed when Compound B is warmed with acidified aqueous potassium dichromate (VI).

Deduce what would be observed when Compound B is warmed with acidified aqueous potassium dichromate (VI).

Describe a test and the expected result to indicate the presence of carbon–carbon double bonds.

Write the equation for the reaction between but-2-ene and hydrogen bromide.

State the type of reaction.

Describe a test and the expected result to indicate the presence of carbon–carbon double bonds.

Write the equation for the reaction between but-2-ene and hydrogen bromide.