2001 - WAEC Chemistry Past Questions and Answers - page 2
11
A mixture of calcium chloride and calcium trioxocarbonate (IV) in water can be separated by
A
evaporation
B
sublimation
C
distillation
D
filtration
correct option: d
Users' Answers & Comments12
Which of the following would dissolve in warm dilute H2SO4 without effervescence, to give a blue solution?
A
Copper turnings
B
Copper (ll) trioxocarbonate (IV)
C
Copper (ll) oxide
D
Copper alloy
correct option: d
Users' Answers & Comments13
In which of the reactions represented by the following equations is HNO3 behaving as a typical acid?
A
CaO + 2HNO3 → Ca(NO3) 2 + H 2O
B
Cu + 4HNO3 → Cu(NO 3)2 + 2H2O + 2NO2
C
S + 6HNO3 → H2SO 4 + 6NO2 + 2H2O
D
P + 5HNO3 → H 3PO 4 + 5NO2 + H2O
correct option: a
Users' Answers & Comments14
A gas was evolved when a sample of gastric juice reacted with sodium trioxocarbonate (IV) . The gas evolved was
A
NH3
B
SO2
C
HCI
D
CO2
correct option: d
Users' Answers & Comments15
It can be concluded that gastric juice
A
contains enzymes
B
is acidic
C
is a mixture
D
has pH value of 7
correct option: b
Users' Answers & Comments16
What does ∆H represent in the following equation ? Cl(g) + e- → CI- (g); ∆H = - 363 kJ mol-1
A
lonization energy
B
Electron affinity
C
Dissociation energy
D
Heat of atomization
correct option: b
Users' Answers & Comments17
Consider the following equation: Ag+ (aq) + CI-(aq) → Ag+CI- (s) ; ∆H = _65.7 kJmol-1. From the equation, it can be deduced that
A
direct combination is involved and the reaction is endothermic
B
a solid is formed and heat is evolved
C
activation energy is high and a catalyst is required
D
the reaction is endothermic and occurs at high temperature
correct option: b
Users' Answers & Comments18
A reaction is represented by the equation below. A2(g) + B2(g) 2AB(g); ∆H = +X kJmol-1 Which of the following statements about the system is correct?
A
The reaction goes to completion at equilibrium
B
The forward reaction is exthermic
C
At equilibrium increase in temperature favours the reverse reaction
D
Pressure has no effect on the equilibrium mixture
correct option: d
Users' Answers & Comments19
What is the oxidation number of nitrogen in AI(NO3)3?
A
+ 1
B
+ 3
C
+ 5
D
+ 6
correct option: c
Users' Answers & Comments20
What is oxidized in the reaction represented by the following equation? 3CU + 8HNO3 → 3Cu(NO3)2 + 2NO + 4H2O
A
Oxygen
B
Hydrogen
C
Nitrogen
D
Copper
correct option: d
Users' Answers & Comments