11.1 Introduction to Organic Chemistry, Set B To print: Ctrl + P, paper A4, margins Default.
Learners' AlleyDesigned by Khow Willard
11.1

Introduction to Organic Chemistry

Set BExam practice
Name
Time 1 hour
Total 23 marks

A Data Booklet may be used.

A

Multiple choice

3 marks
1

Menthone is a component in mint oil.

Which statements about menthone are correct?

1It has a molecular formula of C10H18O.2It has a maximum of 4 stereoisomers.3The carbon bonded to the oxygen is a nucleophilic site.
A1 and 2 only
B1 and 3 only
C2 and 3 only
D1, 2 and 3
Answer [1]

Source: 2022 HCI J1 Promo P1 Q16

2

CommonWhich molecule is not optically active?

A
B
C
D
Answer [1]

Source: 2022 HCI J1 Promo P1 Q17

3

TPI is an enzyme that is essential for energy production. It catalyses the following reaction.

 —TPI→ 

What type of reaction is the overall process?

Aisomerisation
Boxidation
Creduction
Delimination
Answer [1]

Source: 2024 CJC J2 Prelim P1 Q19

B

Structured questions

20 marks
4

3,4-dimethylhexane, , exists as three different types of molecule. Molecule X rotates plane polarised light to the right. Molecule Y rotates plane polarised light to the left. Molecule Z has no effect on plane polarised light.

(a)
Deduce the isomeric relationship between molecules X and Y. Explain your reasoning.
[1]
(b)
Draw the 3-dimensional structure of molecule Z, showing its stereochemical formula. Hence, explain why Z has no effect on plane polarised light.
[2]

Source: 2024 DHS J2 Prelim P3 Q2(b)(iv) and (v)

5
The carbon atom in CO2 is sp hybridised. Explain what is meant by sp hybridisation with reference to the carbon atom in CO2.
[1]

Source: 2024 DHS J2 Prelim P3 Q2(c)(i)

6
Benzoyl chloride, C6H5COCl, contains a benzene ring in its structure. Describe and explain the shape of benzene. In your answer, include the shape and bond angle around each carbon atom, the hybridisation of the carbon atoms, and how orbital overlap forms σ and π bonds between the carbon atoms.
[3]

Source: 2024 VJC J2 Prelim P3 Q3(a)(iii)

7

CommonName each of the following reactions as addition, elimination or substitution.

(a)
CH3CH=CHCH3 + H–H → CH3CH2CH2CH3   (Pd catalyst)
[1]
(b)
CH3CH2CH2OH → CH3CH=CH2 + H–OH   (conc. H2SO4, 170 °C)
[1]
(c)
C6H5CH3 + Cl–Cl → C6H5CH2Cl + H–Cl   (uv light)
[1]
(d)
C6H5CH2CH2Br → C6H5CH=CH2 + H–Br   (NaOH (alc), reflux)
[1]
(e)
C6H6 + CH3CH2Cl → C6H5CH2CH3 + H–Cl   (AlCl3)
[1]

Source: EJC 2022 JC1 Introduction to Organic Chemistry Tutorial, Q5

8
State which type of stereoisomerism C6H5CH(OH)CH=CH2 shows, mark any chiral carbon with an asterisk, and draw the stereoisomers.
[2]

Source: RJC H2 Chemistry Tutorial 10 (Introduction to Organic Chemistry), Q6(e)

9
Suggest why a water molecule can act as a nucleophile.
[1]

Source: 2025 EJC J2 Prelim P2 Q5(b)(i)

10
CommonSuggest which organic acid, CH2ClCH2CO2H or CH3CH2CO2H, is the stronger acid. Explain your reasoning.
[1]

Source: 2024 VJC J2 Prelim P3 Q5(b)(iv)

11
ChallengeThe structural formulae of X, CH3CH(OH)C3H7, and Y, CH3CH=CHC2H5, are ambiguous in that each represents more than one compound. Draw structural formulae to illustrate the four isomers that formula X represents and the two isomers that formula Y represents. In each case, identify the type of isomerism involved.
[4]

Source: EJC 2022 JC1 Introduction to Organic Chemistry Tutorial, Q9