HYDROCARBON ISOMER QUIZ

1. Structural isomers have the same molecular formula but different ….
a. molecular mass
b. structural formula.
c. number of atoms
d. empirical formula
e. atomic structures

2. n-butane and isobutane have different ….
(1) structural formulae
(2) physical properties
(3) chemical properties
(4) molecular formulase

a. (1), (2), (3)
b. (1), (3)
c. (2), (4)
d. (4)
e. (1), (2), (3), (4)

3. Butane and isobutane are structural isomers, compounds with the same molecular formula but different structural formulas. Because these isomers have different structures, they have different ….
a. mass
b. volume
c. boiling point
d. molecular mass relative
e. mass’ percentage of elements

4. How many different structural isomers are there for a hydrocarbon with the formula C6H14?
a. 1
b. 2
c. 3
d. 4
e. 5

5. Which possible formula is an isomer of pentane?
a. 1-methylbutane
b. 2-methylbutane
c. 1,2-dimethylbutane
d. 2,2-dimethylbutane
e. 3-methylbutane

6. The names of two structural isomers of C6H14 are ….
a. 2-methylpentane and 2,2-dimethylbutane
b. hexane and 2-methylpentane
c. 2,2-dimethylbutane and hexane
d. 2-methylbutane and 2,2-dimethylpropane
e. 2,3-dimethylbutane and 1,3-dimethylbutane

7. The following pairs which isomers are ..
a. n-heptane and cycloheptane
b. 2-methylpentane and n-pentane
c. 3-ethylpentane and 3-ethylheptane
d. 3-ethylpentane and 2-methyl heptane
e. 3-methylpentane and3-methylbutane

8. Which of the following pairs represent structural isomers?
a. propane and butane
b. 2-methylbutane and butane
c. 2-methylpropane and propane
d. 2-methylpentane and 2,3-dimethylbutane
e. 2,2-dimethylpentane and 2,2-dimethylbutane

9. Hexane, C6H14, has how many structural isomers, and how many of these are branched hydrocarbons?
a. 3 structural isomers, 1 branched
b. 4 structural isomers, 2 branched
c. 4 structural isomers, 3 branched
d. 5 structural isomers, 3 branched
e. 5 structural isomers, 4 branched

10. Which pair of compounds are C5H12?
a. n-pentane and 1-methylbutane
b. 1-methylbutane and 2-methylbutane
c. 2-methylbutane and 3-methylbutane
d. 2-methylbutane and 2,2-dimethylpropane
e. 1,2-dimethylpropane and 2,2-dimethylpropane

11. How many structural isomers does pentane have?
a. 2
b. 3
c. 4
d. 5
e. 6

12. Including pentane itself, how many chain isomers can pentane be drawn as?
a. 2
b. 3
c. 4
d. 5
e. 6

13. The isomer of pentane is ….
a. C(CH3)4
b. CH3 – (CH2)2 – CH3
c. CH(CH3)2 – CH2 – CH2 – CH3
d. CH3 – CH2 – (CH3) – CH3
e. CH3 – (CH2)3 – CH(CH3)2

14. The following compounds are isomers of hexane, except ….
a. 3-methyl pentane
b. 2,2 – dimethyl propane
c. 2,3 – dimethyl butane
d. 2-methylpentane
e. 2,2 – dimethyl butane

15. The special type of isomers for alkane group is ….
a. chain isomers
b. geometric isomers
c. positional isomers
d. functional isomers
e. structural isomers

16. 2-methyl-1-propene is chain isomer of ….
a. 1-propene
b. 1-butene
c. 2-butene
d. 2-methyl-1-butene
e. 2-methyl-1-pentene

17. Which compounds are classified as chain isomers?
a. ethene and propene
b. 2-butene and 2-pentene
c. propene and 2-methyl-1-propene
d. 2 metil-1-propena and 2 metil-1-butena
e. 5-ethyl-2-methyl-3-heptene and 2,2,5,5-tetra methyl-3-heksene

18. Positional isomer of 1-hexene is ….
a. 2-hexene
b. 1,2-hexadiene
c. 2-methylpentene
d. 3-methylpentene
e. 2,3-dimethylbutene

19. 1-pentene and 2-pentene can be classified as ….
a. chain isomers
b. geometric isomers
c. positional isomers
d. functional isomers
e. structural isomers

20. How many isomers are there of C5H11Cl?
a. Five
b. Six
c. Seven
d. Eight
e. Nine

21. 1-chlorobutane and 2-chlorobutane are ….
a. chain isomers
b. geometric isomers
c. positional isomers
d. functional isomers
e. structural isomers

22. Both chain and positional isomers can be shown by …
a. 1-propene and 1-butene
b. 1-butene and 2-butene
c. 1-butene and 2-methyl-1-propene
d. 1-pentene and 2-methyl-1-butene
e. 1-pentene and 2-methyl-2-butene

23. Cyclobutane (a four carbon ring with all carbon-carbon single bonds and having the molecular formula C4H8 is an isomer of ….
a. butyne
b. butane
c. 1-butene
d. 2-methylpropane
e. butadiene

24. Cyclobutane and 2-butene can be classified as … isomers.
a. chain
b. position
c. function
d. geometric
e. optic

25. Functional isomers can be found in the following compounds. The correct answer is ….
(1) alkene
(2) alkyne
(3) cycloalkane
(4) alkadiene

a. (1) and (2)
b. (1) and (3)
c. (2) and (3)
d. (1) and (4)
e. (3) and (4)

26. 1,3-butadiene is functional isomer with ….
a. 1-butyne
b. 1,3-dibutyne
c. 2-methylpropene
d. 1-butene
e. 2-butene

27. CH3CH=CHCH2CH=CHCH3 is functional isomer with ….
a. 2,5-heptadiene
b. 1,2-heptadiene
c. 5-methyl-1,2-hexadiene
d. 1-methyl-cyclohexane
e. 2-heptyne

28. Which of the following could represent a compound that exhibits geometrical isomerism?
a. C3H6
b. C3H8
c. C4H8
d. C4H10
e. Benzene

29. What feature of the C=C bond in alkenes causes cis/trans isomerism?
a. Its weight
b. Its length
c. Its strength
d. The fact it cannot be broken
e. The fact it is difficult to rotate the bond

30. The following compounds have geometrical isomers, except ….
a. 2-butene
b. 2-methyl-2-butene
c. 2-hexene
d. 3-hexene
e. 2-methyl-3-hexene

31. The name of the isomer of 2-butene with the methyl groups on opposite sides of the double bond is ….
a. 2-butene
b. cis-2-butene
c. trans-2-butene
d. dimethylethylene
e. 2,2-dimethylethylene

32. Which of the following alkenes can have cis-trans isomers?
1. 1-butene
2. 2-butene
3. 2-methyl-1-propene

a. 1 only
b. 2 only
c. 3 only
d. 1 and 2
e. 1, 2, and 3

33. The possible isomers of 2,3-dichloro-2-butene are ….
(1) 1,2-dichloro-2-butene
(2) 2,3-dichloro-1-butene
(3) Cis-1,2-dichloro-2-butene
(4) Trans-1,2-dichloro-2-butene

a. (1), (2), (3)
b. (1), (3)
c. (2), (4)
d. (4)
e. (1), (2), (3), (4)

34. What is the best name for the molecule below?





a. cis-4-methyl-2-hexene
b. trans-4-methyl-2-hexene
c. cis-4-ethyl-2-pentene
d. trans-2-ethyl-3-pentene
e. cis-2-ethyl-3-pentene

35. The above line formula has ….

a. 9 carbon atoms, one double covalent bond, 5 single covalent bonds, 14 hydrogen atoms
b. 7 carbon atoms, one double covalent bond, 5 single covalent bonds, 14 hydrogen atoms
c. 7 carbon atoms, one double covalent bond, 6 single covalent bonds, 12 hydrogen atoms
d. 7 carbon atoms, one double covalent bond, 4 single covalent bonds, 16 hydrogen atoms
e. 9 carbon atoms, one double covalent bond, 6 single covalent bonds, 16 hydrogen atoms

36. The positional isomer of the above compound is ….

a. 4-methyl-1-hexene
b. 3-methyl-2-hexene
c. 2-methyl-2-hexene
d. 4-methyl-4-hexene
e. 3-methyl-4-hexene

37. Functional isomer of the above compound is ….

a. 1-methylcyclohexene
b. methylcyclohexane
c. 1-methylcyclohexane
d. cis-4-methyl-2-hexene
e. 1-heptyne

38. All isomers of C4H8 are ….
(1) cis-2-butene
(2) trans-2-butene
(3) 2-methylpropene
(4) Cyclobutane

a. (1), (2), (3)
b. (1), (3)
c. (2), (4)
d. (4)
e. (1), (2), (3), (4)

39. For a carbon atom to exhibit chirality, what feature must it possess?
a. Be attached to an oxygen atom
b. Have a multiple bond attached to it
c. Have a non-rotating C=C double bond
d. Have four different groups attached to it
e. Be attached to a highly electronega-tive atom such as fluorine, oxygen or nitrogen

40. 2-chlorobutane has an optical isomer, because ….
a. it is a hydrocarbon
b. it contains one chlorine atom
c. it consists of C, H, and Cl atoms
d. it contains 4 carbon atoms, 9 hydrogen atoms, and one chlorine atom
e. it has one asymmetrical carbon atom

41. The formula of 2-chlorobutane is ….
a. CH3CHClCH3
b. CH3CH2CH2CH2Cl
c. CH3CH2CHClCH2Cl
d. CH3CH2CHClCH3
e. CH2ClCH2CHClCH3

42. Alkanol is an organic compound which has … as a functional group.
a. – H
b. – O –
c. – OH
d. – C – C –
e. – C – O –

43. Other compounds that similar with 2-chlorobutane is ….
a. 2-butanol
b. 2-butene
c. 2-butyne
d. 1,2-butadiene
e. cyclobutane

44. The formula of 2-butanol is ….
a. CH3CHOHCH3
b. CH3CH2CHOHCH3
c. CH3CH2CH2CH2OH
d. CH3CH2CHOHCH2OH
e. CH2OHCH2CHOHCH3

45. One of the following compounds which has an asymmetrical carbon atom is ….
a. 3-pentanol
b. 2-pentene
c. 2-pentanol
d. 2-methyl-2-pentanol
e. 3-methyl-3-pentanol

46. 2-butanol has a variety of isomers. These are ….
(1) position
(2) function
(3) chain
(4) optic

a. (1), (2), (3)
b. (1), (3)
c. (2), (4)
d. (4)
e. (1), (2), (3), (4)