Organic Chemistry unit formative...

Name: ________________________ Class: ___________________ Date: __________ ID: A

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Organic Chemistry unit formative exam

Multiple ChoiceIdentify the choice that best completes the statement or answers the question.

1. Which of the following statements is true about polymers?a. All polymers are macromolecules.b. All polymers are inorganic substances.c. All macromolecules have monomers.d. All polymers have only one kind of monomer.

2. The following structure shows a condensation polymer of polyethylene terephthalate fibres.

What type of linkage is present between the monomers?a. Ester linkage c. Halide linkageb. Amide linkage d. Ether Linkage

3. Teflon, an addition polymer, is quite flexible and is resistant to solvents. It remains stable up to 598 K. Suchpolymers are used as coating in non-stick utensils and gaskets. The structure of this polymer is given by:

The monomer unit of this polymer isa. difluoroethane c. diflouroetheneb. fluoroethane d. tetrafluoroethene

4. Which of the following reactions is an elimination reaction?a. CH3 – CH2 – C º CH + H2à CH3 – CH2 CH = CH2

b. C2H5 OH + CH3COOHà CH3COOC2H5 + H2Oc. CH3CH(OH)CH3à CH3CH = CH2 + H2Od. CH3OH + O2à CO2 + 2H2O

Name: ________________________ ID: A

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5. The function group in methanol is:a. – OH

b.

c. – X (X is a halogen)

d.

6. Use the following information to answer the next question.

An unsaturated compound is passed into dilute sulfuric acid in the presence of mercury(II)sulfate as a catalyst, forming the unstable compound ethen–1–ol, CH2 = COH.

This process represents a/ana. addition reaction c. combustion reactionb. substitution reaction d. elimination reaction


The compound that contains hydroxyl group as its functional group isa. (i) c. (iii)b. (ii) d. (iv)

Name: ________________________ ID: A

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8. The functional group present in the compound below is:

a. carboxyl group c. hydroxyl groupb. halogen group d. ester group


The functional group present in the given structure isa. hydroxyl group c. carboxyl groupb. ester group d. alkenyl group


The IUPAC name of the given compound isa. pentanoic acid c. propyl methanoateb. butanoic acid d. 2 – oxy butan-1-ol

Name: ________________________ ID: A

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When this compound reacts with an organic compound having a hydroxyl group, in the presence of acidicmedium, such a reaction is a/ana. addition reaction c. elimination reactionb. condensation reaction d. substitution reaction


In an experiment, cyclohexanol is treated with phosphoric acid at a temperature of 110oC –160oC. In this process, a compound ‘x’ and a water molecule are produced.

The functional group present in the product formed in this process isa. carboxyl group c. alkene groupb. alkyne group d. hydroxyl group


The above structure is an isomer ofa. butane c. heptaneb. pentane d. hexane

Name: ________________________ ID: A

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14. Which of the following structures does not represent an isomer of hexane?

a.

b.

c.

d.


Four unsaturated compounds W, X, Y and Z, within the same homologous series; the number ofcarbon atoms increases from W to Z.

Which of the given compounds has the lowest boiling point?a. W c. Xb. Y d. Z


In a chemical experiment, 1, 1, 2, 2- tetrabromoethane is treated with alcoholic zinc to producean unsaturated substituted hydrocarbon.

This process represents an example ofa. substitution reaction c. elimination reactionb. addition reaction d. combustion reaction

17. Which of the following carboxylic acids is the least soluble in water?a. CH3 COOH c. C3H7COOHb. CH2 H5COOH d. C4 H9 COOH

18. The IUPAC name of compound CH3C(CH3)CHCH3 isa. 2–methylbut–3–ene c. 2–methylbut–2–eneb. 3–methylbut–2–ene d. 3–methylbut–3–ene

Name: ________________________ ID: A

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19. Consider the following structure of a compound:

The compound is an isomer ofa. propane c. propyneb. propene d. cyclopropene


Chloroform (CHCl3) is generally used as an anesthesia in medical treatment. It is also used inthe chemical industry to produces dyes and pesticides. It is generally obtained by the action ofchlorine on a hydrocarbon in the presence of sun rays.Cl2 + Xà Chloroform

If X is the hydrocarbon used for the production for chloroform, compound X isa. methane c. ethaneb. ethene d. propyne


When compound X reacts with compound Y in an acid, a sweet-smelling compound is produced.When compound X is treated with sulfuric acid, an alkene and water are produced.

Compound X is a/an:a. alcohol c. alkyneb. carboxylic acid d. alkane

Name: ________________________ ID: A

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22. The structural formula of 2,2,4-trimethylpentane is

a.

b.

c.

d.

23. When propene is treated with bromine water, Br2(l), in the presence of carbon tetrachloride as a catalyst, theproduct is:a. 1,2–dibromopropane c. 2–bromopropaneb. 2,2–dibromopropane d. 1–bromopropane

24. One of the products formed when pentene reacts with hydrogen bromide, HBr, is 2-bromopentane. What typeof reaction is this?a. elimination c. substitutionb. addition d. methylation

25. In an experiment, propan-1-ol is made to react with propanoic acid, in the presence of concentrated sulfuricacid as a catalyst. The product is:a. propyl butanoate c. propyl propanoateb. ethyl propanoate d. butyl propanoate

Name: ________________________ ID: A

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The combustion reaction propene is shown below:

aCH3 – CH = CH2 + bO2à cCO2 + dH2O

The respective values of variables a, b, c and d area. 2, 4, 6, 5 c. 2, 8, 5, 7b. 3, 4, 3, 6 d. 2, 9, 6, 6


Consider the following additon reaction:CH3 – CH2 - C º C – CH3 + 2H2 CH3 – CH2 – CH2 – CH2 – CH3

The IUPAC name of the first reactant isa. pent–2–yne c. pent–2–eneb. pent–3–yne d. pent–3–ene

28. The IUPAC name of the following organic compound is

a. 1, 2-dichlorobenzene c. 1, 5-dibenzochlorideb. 1, 3-dichlorobenzene d. 1, 3-dibenzochloride

29. Which of the following molecular structures represents 1,3-dimethylcyclobutane?

a. c.

b. d.30. In an organic compound, two methyl groups are found at the third and sixth positions and two double bonds

exist at the first and fourth positions. If this compound has a ring structure with minimum possible number ofcarbon atoms, the IUPAC name of this compound will bea. 3,6-dimethylpent-1,4-diene c. 3,6-dimethylhept-1,4-dieneb. 3,6-dimethylhex-1,4-diene d. 3,6-dimethyloct-1,4-diene

Name: ________________________ ID: A

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31. The IUPAC name of the molecule is:

a. 3-ethyl-2,4,4-trimethylhexane c. 4-ethyl-3,3,5-trimethylhexaneb. 3-ethyl-2,4-trimethylhexane d. 4-ethyl-3,5-trimethylhexane


Nonane is a saturated hydrocarbon with the empirical formula C9H20. This hydrocarbon canexhibit 35 different isomers. One of these isomers is given below.

The IUPAC name of this isomer isa. 6-methylnonane c. 6-methyloctaneb. 3-methylnonane d. 3-methyloctane


Ethylene glycol acts as antifreeze and is used in automobiles and computers. It is also used forpreserving body organs and in the manufacture of capacitors. Its structure is shown below.

The IUPAC name of this compound isa. ethanol c. 1-hydroxyethane-1,2-diolb. ethane-1,2-diol d. 2,2-dihydroxyethane-1,2-diol


The molecular structure of compound ‘x’ is given below:

This fruit-scented compound is generally used in ice creams and other food stuffs as a flavouringagent.

The IUPAC name of compound ‘x’ isa. propyl ethanoate c. ethyl propanoateb. propane ethanoate d. ethane propanoate

Name: ________________________ ID: A

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The molecular structure of a compound is given below:

The IUPAC name of this compound isa. non-5-yne c. oct-4-yneb. hept-3-yne d. dec-5-yne


Cellular respiration, the process used by organisms to obtain energy fromfood, is a series of organic reactions that produces carbon dioxide, water, andenergy. In this process, carbohydrate and fat are oxidized to produce carbondioxide and water molecules, and energy is released.

+ à + + Energy

Which of the following organic reactions represents this process?a. Addition reaction c. Elimination reactionb. Substitution reaction d. Combustion reaction


William treats compound ‘x’ with concentrated sulfuric acid to producecompound ‘y’. In this process, compound ‘x’ undergoes an eliminationreaction. Compound ‘x’ is also used to manufacture esters, whereascompound ‘y’ on hydrogenation gives a saturated hydrocarbon.

The functional group present in compound ‘x’ isa. hydroxyl c. esterb. alkenyl d. halogen


(ii)

How many functional groups are there in compound (ii)?a. One c. Threeb. Two d. Four

Name: ________________________ ID: A

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39. Which of the following compounds is the most soluble in water?a. CH3 – CH2 – OH c. CH3 – OHb. CH3 – CH2 – CH2 – OH d. CH3 – CH2 – CH2 – CH2 – OH

40. Alkyl halides are hydrocarbons that contain at least one halogen atom.

What is the name of this alkyl?a. 2,5-dichloro-1-methylcyclohexane c. 4,6-dichloro-1-methylcylclohexaneb. 1,3-dichloro-4-methylcyclohexane d. 1,5-dichloro-2-methylcyclohexane

41. Structural isomers are compounds that have ______ empirical molecular formula and ______ structuralformula. The statement above is completed by the information given in a row of the table below:a. the same the same c. the same differentb. different the same d. different different


Methyl benzoate has a pleasant smell and is used in the perfumery industry. It is soluble inorganic solvents and is sometimes used in pesticides because insects are attracted to its scent.

Its structure is:

a. c.

b. d.

Name: ________________________ ID: A

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Glycerol is a colourless and odourless liquid with a sweet taste. It contains three hydroxylgroups and it is soluble in water.

The structure of glycerol is:

IUPAC of glycerol is:a. Propane-1,2,3-triol c. Propane-1,2,3-diolb. Propan-1,2,3-oic acid d. Propan-1,2,3-oate

44. Four organic compounds belonging to different functional groups are:

Compound Functional group1.

2.

3.

4.

Which of the above given compounds has the highest boiling point?a. 1 c. 3b. 2 d. 4


An compound has a molecular formula CH3CH2COOH. It is produced from ethyl alcohol andcarbon monoxide.

What is the name of the acid?a. Ethanoate c. Propanoic acidb. Ethanoic acid d. Propanol

Name: ________________________ ID: A

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46. Two isomers of C4O2H8 are:

and

The names of both these compounds area. methyl propanoate and propyl methanoateb. propyl methanoate and methyl methanoatec. propyl propanoate and methyl propanoated. propyl methanoate and methyl propanoate

47. An organic compound with the molecular formula C3H7Br(l) is a colourless liquid used in organic synthesis.The structure of the compound is:

What is the name of the compound?a. Bromopropane c. 2-Bromopropaneb. Bromoprop-2-ane d. 2-Propanebromide


Organic compounds are classified according to the functional group as1. Alcohol2. Alkyl3. Carboxylic acid4. Ester

Of the above four organic families, compounds i and ii are capable of forming hydrogen bonds. Thestatement given above is completed by the information given in the row:

Row i iiA 1 2B 2 3C 3 4D 2 4

a. A c. Cb. B d. D

Name: ________________________ ID: A

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In an experiment, ethyl bromide is treated with KOH to give an organic compound “z”.

This above reaction is a type of a/ana. substitution reaction c. elimination reactionb. addition reaction d. esterification reaction


A scientist treated propene with bromine in the presence of carbon tetrachloride. The results was1,2-dibromoprapane.

This above reaction is a type of a/ana. elimination reaction c. combustion reactionb. addition reaction d. substitution reaction

51. Consider the following organic reactions:1. C6H14(l) + HNO3(l) C6H13NO2(l) + H2O(l)2. CH4(g) + 2O2(g) ® CO2(g) + 2H2O(g)3. C2H2Br4(l) + 2Zn(s) ® HCºCH(g) + 2ZnBr2(aq)

4. CH3COOH(l) + C2H5OH(l) CH3COOC2H5(l) + H2O(l)

Which of these reactions represents a combustion reaction?a. 1 c. 3b. 2 d. 4

52. Name the following compound.

a. 4-ethyl-3-methylheptane c. 3-propyl-4-methylhexaneb. 4-methyl-3-propylhexane d. 4-ethyl-3-methylhexene

Name: ________________________ ID: A

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Numeric Response

53. A functional group is a special arrangement of atoms that is mainly responsible for the chemical behaviour of amolecule. Several functional groups are given below:

1.

2.

3. – C º C –

4.

The correct order of the above functional groups, such that they represent the hydroxyl group, alkanes, alkynes,and alkenes, respectively, is _______, _______, _______, and _______.

54. An alcohol is a hydrocarbon derivative with the functional group – OH. Several structural formulae are givenbelow:

Number Structural Formula1.

2. HO – CH2 – CH2 – OH3. CH3 – CH2 – OH4. CH3 – OH

The correct order of the structural formulae corresponding to the names ethanol, propane-2-ol, methanol, andethan-1,2-diol, respectively, is ________, ________, ________, and ________.

Name: ________________________ ID: A

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55. Alkyl halides are hydrocarbons containing halogen atoms. The structural formulae of several alkyl halides aregiven below.1.

2.

3.

4.

The correct order of the structural formulae, such that they represent the names bromobenzene,1,3-dibromo-4-methylcyclohexane, 1-bromo-2-methylbenzene, and 1,3-dibromo-5-methylhexane, respectively,is ________, ________, ________, and ________.

Name: ________________________ ID: A

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56. Chemists use many different reactions to synthesize specific organic products. Reactions are classified into fourcategories: addition, elimination, combustion, and substitution reactions. Several reactions are shown below.1.

2.

3.

4.

The correct order of the reactions, such that they represent an elimination reaction, an addition reaction, acombustion reaction, and a substitution reaction, respectively, is________, ________, ________, and________.

Name: ________________________ ID: A

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Organic reactions can be classified into four categories: addition, elimination,combustion, and substitution reactions. Each reaction transforms an organiccompound into other organic and/or inorganic compounds.

1. Atoms are removed from an organicmolecule, and double bonds formbetween two carbon atoms.

2. A compound reacts with oxygen toproduce the oxides of the elements thatmake the compound.

3. In alkenes and alkynes, atoms are addedto double or triple bonds.

4. A hydrogen atom or functional group isreplaced by a different functional group

The correct order of the definitions, such that they represent an elimination reaction, substitution reaction,combustion reaction, and addition reaction, respectively, is ________, ________, ________ and ________.

ID: A

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Organic Chemistry unit formative examAnswer Section

MULTIPLE CHOICE

1. AIt is true that all polymers are macromolecules, but not all macromolecules are not polymers.For example: Chlorophyll, a green pigment in the plants, is a macromolecule. However, it is not a polymer,because it does not contain a repeating monomer unit.

2. A3. D

The monomer unit of teflon is tetrafluoroethene, F2C = CF2. The polymerization reaction of teflon is given by

4. CThe following reaction is an elimination reaction as a double bond is produced.CH3CHOHCH3à CH3 CH = CH2 +H2O

5. AAlcohols are characterized by the –OH functional group.

6. AThe given process is an example of an addition reaction and the unsaturated hydrocarbon is ethyne, CH º CH.

7. A8. D

The second compound is an ester, because it has ester linkage.9. C

The given compound contains carboxyl group.

ID: A

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10. BThe given structure can also be represented as

Since there are four carbon atoms and a carboxyl group, the IUPAC name of the compound is ‘butanoic acid’.11. B

Since the given compound contains a carboxyl group, it is a carboxylic acid.The organic compound that contains a hydroxyl group is an alcohol. When a carboxylic acid reacts with analcohol in the presence of concentrated sulfuric acid an ester is formed.

R'(aq) + H2

Therefore, it is an esterification reaction. Since a water molecule is eliminated from the given reaction, thegiven reaction may also be called a condensation reaction.

12. BThe above process can be represented by a chemical reaction in the following way:

In this reaction, a water molecule is eliminated from the cyclohexanol, and cyclohexene is formed. Thefunctional group present in cyclohexene is an alkene group.

13. CThe given structure is

It represents an isomer of heptane. In isomers, the number of carbon atoms always remains the same. Sincethere are seven carbons in the above structure, it represents an isomer of heptane.

14. D15. A

‘W’ has the lowest boiling point, because the boiling point of alkenes and alkynes increases with the increase inthe number of carbon atoms. ‘W’ has the lowest boiling point and ‘Z’ has the highest boiling point.

ID: A

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16. CThis process represents an example of elimination reaction because four bromine atoms are eliminated from themolecule.

17. DThe larger the alkyl portion (carbon tail) of the carboxylic acid, the lower the solubility, since the alkyl portionis non-polar. C4H9COOH is least soluble in water because of its larger non-polar alkyl portion.

18. CThe compound used in the given process is

According to IUPAC rules of naming the organic compounds, the name of the compound is 2-methyl but – 2–ene.

19. BCyclopropane is an isomer of propene, CH3 – CH = CH2. The number of carbon and hydrogen atoms is thesame in both cyclopropane and propene.

20. AChloroform is produced when chlorine molecules attack methane gas in the presence of the sun’s rays.Cl2 + CH3Cl + HCl

CH3Cl + Cl2 CH2Cl2 + HClCH2Cl2 + Cl2 + HCl

Compound X is ‘methane’.21. A

From the given information, the compounds X and Y react with each other to produce an ester (asweet-smelling compound). Therefore, these compounds are an alcohol and a carboxylic acid. When treatedwith sulfuric acid, compound X produces an alkene and water, therefore, compound X is an alcohol

22. AThe structural formula of 2,2,4-trimethylpentane is

.

ID: A

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23. AWhen propene reacts with bromine water, Br2(l), in the presence of carbon tetrachloride as a catalyst, theaddition reaction between propene and bromine molecule takes place, to form 1,2–dibromopropane.

CH2 = CH – CH3

24. B25. C

When propanol reacts with propanoic acid, in the presence of concentrated sulfuric acid,

26. DWhen propane burns amidst sufficient supply of air, it gives carbon dioxide and water. The required chemicalequation for this process is2C3H6 (g) + 9O2 (g)à 6CO2 (g) + 6H2O (g)

Therefore, the values of a, b, c and d are: 2, 9, 6 and 6.27. A

The triple bond is attached to the second and third carbon atoms. According to IUPAC rules for naming organiccompounds, the bond is named for the second carbon atom. Therefore, the IUPAC name of the compound ispent-2-yne.

28. BThe IUPAC name of the given compound is 1,3-dichlorobenzene, because one chlorine atom is attached to thefirst carbon atom and other one is attached to the third carbon atom.

29. ASince the given compound is an alkane, it should not have any multiple bonds. The numbering starts from oneside chain so that the other side chain gets the lowest number.

ID: A

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30. BAs per the information, the compound will look like

31. AThe given structure is

The parent chain is outlined. On the chain are 4 branches, 3 methyl groups and an ethyl group. Using thesmallest numbers possible, the ethyl group is given #3, and the methyl groups are on carbons 2 and 4. Puttogether, the name is 3-ethyl-2,4,4-trimethylhexane

32. D33. B

The structural formula of ethylene is given as following:HO – CH2 – CH2 – OHIt is clear from the above structure that the IUPAC name of ethylene glycol is ethane-1,2-diol.

34. CThe structure of the compound ‘x’ is

According to the IUPAC rules for naming organic compounds, the IUPAC name of compound ‘x’ is ethylpropanoate.

35. D

According to IUPAC rules for naming compounds, the IUPAC name of the given compound is dec-5-yne.

ID: A

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36. DCellular respiration represents a combustion reaction because it involves the production of carbon dioxide andwater molecules along with release of energy.

37. ACompound ‘x’ is used to manufacture esters. Since alcohols and carboxylic acids are used for this purpose, thefunctional group present in the compound ‘x’ is the hydroxyl group.

38. BThere are two functional groups in compound (ii): alkenyl and carboxyl.

39. CShort-chain molecules containing polar carbon–oxygen bonds can form more hydrogen bonds than canlonger-chain molecules. As the length of the carbon chain increases, the number of non-polar bonds increases,and the effect of hydrogen bonding becomes less significant, while London (dispersion) forces that act betweenmolecules becomes significant. As the effect of hydrogen bonding decreases, the solubility decreases.

40. B1,3-dichloro-4-methylcyclohexane

41. C42. A43. A

There are three carbon atoms in a chain, so its root name is propane. It has three hydroxyl groups on eachcarbon atom. So its IUPAC name is propane-1,2,3-triol.

44. CThe presence of C=O and –OH group make the carboxyl group very polar, which allows for hydrogen bonding.Thus, the boiling point of compound 3 (carboxylic acid) is much higher than others. Compound 1 is an alcohol,and its boiling point is higher than compounds 2 and 4 because of hydrogen bonding. Compound 4 is an esterand it cannot form hydrogen bonds. Hence, the boiling point of compound 3 is the highest.

45. CThe name of CH3CH2COOH is propanoic acid.

46. A47. B48. D49. C

It is clear that this is an elimination reaction because it involves the removal of the bromide from the reactant.50. B51. B

A combustion reaction involves the reaction of a hydrocarbon with oxygen gas. In this process, carbon dioxideand water molecules are released along with heat energy.

52. A

NUMERIC RESPONSE

53. 4132Alkanes have C – C single bonds, alkenes have C = C double bonds, alkynes have C º C triple bonds, and the –OH group is the hydroxyl group.

ID: A

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54. 3142When one – OH group is attached to a methyl group, the structure is called methanol. When two alkanecarbons and two – OH groups are attached together; the structure is called ethan-1,2-diol. When athree-alkane-carbon chain and one – OH group are attached together, and the – OH group is attached to thecarbon at the second position, the structure is called propane-2-ol. If two alkane carbons and one – OH groupare attached together, the structure is called ethanol.

55. 3142Compounds 1 and 2 are cyclohexane with two bromine atoms and one methyl group.. Numbering begins at abromine atom and proceeds towards the second bromine and then methyl group. In compounds 3 and 4, theparent compound is benzene, and the numbering starts from benzene and then proceeds towards the methylgroup.

56. 3142In combustion reactions, hydrocarbons burn completely to yield CO2 and water vapour. In addition reactions,atoms are added to a double or triple bond. In elimination reactions, atoms are removed from an organicmolecule, and a double bond forms between the two carbon atoms from which the atoms were removed.. Insubstitution reactions, a hydrogen atom or a functional group is replaced by a different functional group.

57. 1423

Organic Chemistry unit formative...

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