Organic Compounds - Jamb Chemistry Past Questions and Answers

Question 41:

• JAMB 1983

The three-dimensional shape of methane is

A. Hexagonal
B. Trigonal
C. Linear
D. Tetrahedral
E. Cubical

Question 42:

• JAMB 1983

An unknown organic compound X has a relative molecular mass of 180. It is a colourless crystaline solid, readily soluble in water. X contains the elements C, H and O in the atomic ratio 1: 2:1. The compound has a sweet teste and melts on heating. In the presence of yeast and in the absence of air, X is converted to compound Y and a colourless gas. Compound Y reacts with sodium metal to produce a gas Z which gives a 'pop' sound with a glowing splint. Y also reacts with ethanoic acid to give a sweet smelling compound W.
Compound W is

A. A soap
B. An oil
C. An alkane
D. An ester
E. Sucrose

Question 43:

• JAMB 1983

An unknown organic compound X has a relative molecular mass of 180. It is a colourless crystaline solid, readily soluble in water. X contains the elements C, H and O in the atomic ratio 1: 2:1. The compound has a sweet teste and melts on heating. In the presence of yeast and in the absence of air, X is converted to compound Y and a colourless gas. Compound Y reacts with sodium metal to produce a gas Z which gives a 'pop' sound with a glowing splint. Y also reacts with ethanoic acid to give a sweet smelling compound W.
The molecular formula of X is

A. C₁₂H₂₂O₁₁
B. C₆H₁₂O₆
C. C₃H₆O ₃
D. C₇H₁₄O₇
E. C₁₂H₆O₄

Question 44:

• JAMB 1983

C₂H₅ - C = CH₂
CH₃
The correct name of the compound with the above structural formula is

A. 2-methylbut -1-ene
B. 2-methylbut -2-ene
C. 2-methylbutane
D. 2-ethylprop-1 -ene
E. 2-ethylprop-2-ene

Question 45:

• JAMB 1983

How many isomeric forms are there for the molecular formula C₃H₆Br₂?

A. 1
B. 2
C. 3
D. 4
E. 5