2026 IJMB CHEMISTRY PAPER II QUESTIONS

2026 IJMB CHEMISTRY PAPER II QUESTIONS BELOW

2026 IJMB CHEMISTRY PAPER II ANSWERS BELOW

*IJMB-CHEMISTRY*

(1)
(a) C₃H₈O₃
(b) C₃H₈O₃
(c) Propane-1,2,3-triol

*IJMB CHEMISTRY II*

*NUMBER TWO*

(2a)
Nitration reaction (electrophilic substitution)

(2b)
Reduction reaction (reduces aldehydes, ketones, acids, esters, etc.)

(2c)
Oxidation reaction

(2d)
Friedel-Crafts alkylation (methylation of an aromatic ring)

(2e)
Birch reduction (reduction of aromatic rings)

*IJMB CHEMISTRY II*

*NUMBER THREE*

(3a)
Isotopy is the phenomenon whereby atoms of the same element have the same atomic number but different mass numbers due to different numbers of neutrons.

(3b)
(i) ¹²₆C
(ii) ¹³₆C
(iii) ¹⁴₆C

*IJMB CHEMISTRY II*

*QUESTION FOUR*

(4ai)
Stereoisomers are compounds having the same molecular formula and structural formula but differ in the three-dimensional spatial arrangement of atoms or groups within the molecule, thereby giving rise to different properties.

(ii)
They can be distinguished by their optical activity. One stereoisomer rotates plane-polarized light in a clockwise direction while the other rotates it in an anticlockwise direction.

(4b)
When alanine and glycine react, condensation reaction occurs with elimination of water, leading to formation of two dipeptides:

Alanyl-glycine
H₂N–CH(CH₃)–CO–NH–CH₂–COOH

Glycyl-alanine
H₂N–CH₂–CO–NH–CH(CH₃)–COOH

*IJMB CHEMISTRY II*

*NUMBER FIVE*

(5a)
The likely mechanism is free radical substitution.

(5b)
The type of bond fission involved is homolytic fission (homolysis).

(5c)
The number of different structural isomers of C₁₀H₂₁Cl that can be produced is 5.

(5d)

*IJMB CHEMISTRY II*

*NUMBER SIX*

(6a)
4 π electrons

(6b)
4 π electrons

(6c)
2 π electrons

(6d)
0 π electrons

(6e)
2 π electrons

*IJMB CHEMISTRY II*

*NUMBER SEVEN*

(7)
(PICK ANY FIVE)
(i) Methane (CH₄)
(ii) Ethane (C₂H₆)
(iii) Propane (C₃H₈)
(iv) Butane (C₄H₁₀)
(v) Ethylene (Ethene, C₂H₄)
(vi) Propylene (Propene, C₃H₆)
(vii) Butadiene (C₄H₆)
(viii) Benzene (C₆H₆)
(ix) Toluene (C₇H₈)
(x) Xylene

*IJMB CHEMISTRY II*

*NUMBER EIGHT*

(8a)
-NO₂ → Deactivating

(8b)
-SO₃H → Deactivating

(8c)
-OH → Activating

(8d)
-COOH → Deactivating

(8e)
-NH₂ → Activating

*IJMB CHEMISTRY II*

*NUMBER NINE*

(9)
(i) Hexane – C₆H₁₄
(ii) Heptane – C₇H₁₆
(iii) Octane – C₈H₁₈
(iv) Nonane – C₉H₂₀
(v) Decane – C₁₀H₂₂

NUMBER 11