Question Library

Browse, filter, and study verified past examination questions with step-by-step mathematical reasoning.

Launch Interactive Practice
Searching 18,000+ Questions... Sifting topics, KaTeX formulas & verified solutions
Showing 14521–14535 of 29821 verified questions
Sort by:
Chemistry WAEC / WASSCE 2006 Chemical Energetics & Thermochemistry
Consider the reaction represented by the equation: 2SO\(_{2(g)}\) + O\(_{2(g)}\) ⇌ 2SO\(_{3(g)}\); ∆H = - 197 kJmol\(^{-1}\). Which of the following conditions will not increase the yield of sulphur (VI) oxide?
A
Increase in temperature
B
Decrease in temperature
C
Increase in pressure
D
Addition of O2 into the mixture
medium Difficulty
Chemistry WAEC / WASSCE 2006 Electrolysis & Electrochemical Cells
Electrolysis is applied in the following processes except
A
electroplating
B
extraction of aluminium
C
extraction of iron
D
purification of copper
medium Difficulty
Chemistry WAEC / WASSCE 2006 Oxidation, Reduction & Redox Reactions
The oxidation number of iodine in the iodate ion (IO -3) is
A
-5
B
-1
C
+1
D
+5
medium Difficulty
Chemistry WAEC / WASSCE 2006 Stoichiometry, Mole Concept & Volumetric Analysis
Metals can be extracted from their ores by a process involving
A
reduction
B
oxidation
C
hydrolysis
D
decomposition
medium Difficulty
Chemistry WAEC / WASSCE 2006 Stoichiometry, Mole Concept & Volumetric Analysis
Consider the reaction: 2AI(s) + 6H+ (aq) → 2AI3+ (aq) + 3H2(g). What is the total number of moles of electrons transferred from the aluminium atoms to the hydrogen ions?
A
3
B
4
C
5
D
6
medium Difficulty
Chemistry WAEC / WASSCE 2006 Stoichiometry, Mole Concept & Volumetric Analysis
In the reaction represented by the equation. 5Fe 2+ (aq) + MnO- 4(aq) + 8H+ (aq) → 5Fe3+(aq) + Mn2+(aq) + 4H2O(l) which species is reduced?
A
Fe2+
B
MnO-4
C
H+
D
Fe3+
medium Difficulty
Chemistry WAEC / WASSCE 2006 Stoichiometry, Mole Concept & Volumetric Analysis
Which of the following industrial processes is chlorines not used?
A
Production of polyvinylchloride (PVC)
B
Manufacturing of hydrochloric acid
C
Manufacturing of common salt
D
Manufacturing of domestic bleach
medium Difficulty
Chemistry WAEC / WASSCE 2006 Acids, Bases, pH & Salts
What type of reaction occurs between vegetable oil and plant ash extract?
A
Displacement
B
Dehydration
C
Neutralization
D
Saponiflication
medium Difficulty
Chemistry WAEC / WASSCE 2006 Organic Chemistry II: Functional Groups, Polymers & Biomolecules
Which of the following compounds is an alkanoate?
A
CH3COOH
B
CH3COOCH3
C
CH3CH2OH
D
CH3CH2COOH
medium Difficulty
Chemistry WAEC / WASSCE 2006 Stoichiometry, Mole Concept & Volumetric Analysis
What is CaHb in the following equation? C a H b + 5O2 → 3CO 2 + 4H2O
A
C 3H4
B
C3H6
C
C3H8
D
C 5H 10
medium Difficulty
Chemistry WAEC / WASSCE 2006 Air & Environmental Chemistry
Greenhouse effect can be reduced by controlling
A
water evaporation
B
burning wood and fossil fuel
C
the use of aerosols
D
the use of artificial fertilizers
medium Difficulty
Chemistry WAEC / WASSCE 2006 Air & Environmental Chemistry
Waste plastics accumulate in the soil and pollute the environment because plastic materials are
A
insoluble in water
B
non -biodegradable
C
easily affected by heat
D
inflammab,le
medium Difficulty
Chemistry WAEC / WASSCE 2006 Metals, Transition Elements & Extraction
Which of the following substance is an ore of iron?
A
Bauxite
B
Cassiterite
C
Haematite
D
Steel
medium Difficulty
Chemistry WAEC / WASSCE 2006 Electrolysis & Electrochemical Cells
The ammonium compound used in the manufacture of dry cells is
A
NH4NO3
B
(NH4)SO4
C
NH4Cl
D
(NH4)2CO3
medium Difficulty
Chemistry WAEC / WASSCE 2006 Stoichiometry, Mole Concept & Volumetric Analysis
Which of the following equations represents a substitution reaction?
A
C 2H10(g) + CI 2(g) → C4H9 CI(g) + HCI(g)
B
C 2H4(g) + HCI (g) → C 2H5 CI(l)
C
C2H2(g) + 2H 2(g) → C 2H6(g)
D
C 3H4(g) + 402(g) → 3CO2(g) + 2H 2O(g)
medium Difficulty
Page 969 of 1989