2014 - JAMB Chemistry Past Questions and Answers - page 5
41
The polymer used in making car rear lights is
A
perspex
B
bakeelite
C
polystyrene
D
polyacrylonitrile
correct option: a
Users' Answers & Comments42
CH3COOC2H5(1) + H2O(1) ⇌ CH 3COOH (aq) + C 2H 5OH (aq)
The purpose of H+ in the reaction above is to
The purpose of H+ in the reaction above is to
A
increase the yield of products
B
maintain the solution at a constant PH
C
increase the rate of the hydrolysis
D
decrease the rate of the reverse reaction
correct option: a
Users' Answers & Comments43
A hydrocarbon has an empirical formula CH and a vapour density of 39. Determine its molecular formula.
[C = 12, H = 1]
[C = 12, H = 1]
A
C2H6
B
C3H8
C
C3H4
D
C6H6
correct option: d
molecular mass = 2 x vapour density
= 2 x 39 = 79
∴ Cn Hn = 78
12n + 1n = 78
13n = 78
n = \(\frac{78}{13}\) = 6
∴ Cn Hn = C 6H 6
Users' Answers & Comments= 2 x 39 = 79
∴ Cn Hn = 78
12n + 1n = 78
13n = 78
n = \(\frac{78}{13}\) = 6
∴ Cn Hn = C 6H 6
44
Polystyrene is widely used as packaging materials for fragile objects during transportation because of its
A
ligjtness
B
low density
C
high density
D
high compressibility
correct option: d
EPS is known as one of the world’s most effective and lightweight insulation and packaging materials. It has low thermal conductivity and is moisture resistant, so it is often used as insulation against changing temperatures. Its high compressive strength gives it excellent shock absorption properties, making it an efficient packaging material.
Users' Answers & Comments45
The process of converting linear alkanes to branched chain and cyclic hydrocarbons by heating in the presence of a catalyst to improve the quality of petrol is referred to as
A
refining
B
craching
C
reforming
D
blending
correct option: c
Users' Answers & Comments46
The petroleum fraction that is used in heating furnaces in industries is
A
diesel oil
B
gasoline
C
kerosene
D
lubricating oil
correct option: a
Users' Answers & Comments47
A
2-bromo-3-chlorobutanol
B
3-bromo-2-chlorobutanol
C
3-chloro-2-bromobutanol
D
2-chloro-3-bromobutanol
correct option: d
Users' Answers & Comments48
A
purify the gas
B
dry the gas
C
liquefty the gas
D
remove odour
correct option: b
Users' Answers & Comments49
A
O2
B
SO2
C
HCI.
D
H2
correct option: c
Users' Answers & Comments50
A
heat of reaction
B
activation energy
C
free energy
D
entropy of reaction
correct option: a
Users' Answers & Comments