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Chemistry
WAEC / WASSCE 1994
Periodic Table & Periodicity
Polyatomicity is illustrated by molecules of
A
sulphur
B
carbon (IV) oxide
C
noble gases
D
liquefied oxygen
E
liquefied nitrogen
medium Difficulty
Verified Correct Answer: Option A
Chemical Principles & Mechanism
No expanded working has been attached for this question yet. The verified answer is Option A.
Source: Myschool Past Questions Archive (Record #36342)
Chemistry
WAEC / WASSCE 1994
Electrolysis & Electrochemical Cells
Calcium is usually extracted by the electrolysis of its
A
trioxonitrate (V)
B
tetraoxosulphate (IV)
C
oxide
D
hydride
E
chloride
medium Difficulty
Verified Correct Answer: Option E
Chemical Principles & Mechanism
No expanded working has been attached for this question yet. The verified answer is Option E.
Source: Myschool Past Questions Archive (Record #36344)
Chemistry
WAEC / WASSCE 1994
Organic Chemistry I: Hydrocarbons & Crude Oil
When water is dropped on calcium carbide, the gaseous product is an
A
alkane
B
alkene
C
alkyne
D
alkanol
E
alkanal
medium Difficulty
Verified Correct Answer: Option C
Chemical Principles & Mechanism
No expanded working has been attached for this question yet. The verified answer is Option C.
Source: Myschool Past Questions Archive (Record #36350)
Chemistry
WAEC / WASSCE 1994
Stoichiometry, Mole Concept & Volumetric Analysis
Solution
Mg\(_2\) + 2HCI\(_{(aq)}\) → MgCI\(_{2(g)}\) + H\(_{2(g)}\).
From the equation above what mass of hydrogen would be produced if 12.0 g of magnesium reacted completely with dilute hydrochloric acid? (H = 1, Mg = 24)
A
1.0g
B
2.0g
C
6.0g
D
12.0g
E
24.0g
medium Difficulty
Verified Correct Answer: Option A
Chemical Principles & Mechanism
Mg\(_2\) + 2HCI\(_{(aq)}\) → MgCI\(_{2(g)}\) + H\(_{2(g)}\).
24g Mg reacts with 2g H
1g Mg = \(\frac{2}{24}\)g H
12g Mg = \(\frac{2}{24} \times 12\)g H
= 1g H.
Source: Myschool Past Questions Archive (Record #36351)
Chemistry
WAEC / WASSCE 1994
Periodic Table & Periodicity
The positive of an element in the Periodic Table is determined by
A
its density
B
its atomic radius
C
its relative atomic mass
D
the number of protons in its atom
E
the number of neutrons in its atom
medium Difficulty
Verified Correct Answer: Option D
Chemical Principles & Mechanism
No expanded working has been attached for this question yet. The verified answer is Option D.
Source: Myschool Past Questions Archive (Record #36352)
Chemistry
WAEC / WASSCE 1994
Atomic Structure, Orbitals & Nuclear Chemistry
Solution
Which of the following electronic structures belongs to a noble gas?
A
1s22s2
B
1s 22s22p4
C
1s22s22p63s23p6
D
1s22s22p2
E
1s22s22p 63s23p3
medium Difficulty
Verified Correct Answer: Option C
Chemical Principles & Mechanism
\(1s^22s^22p^63s^23p^6\)
Which is Argon = 2,8,8
Source: Myschool Past Questions Archive (Record #36356)
Chemistry
WAEC / WASSCE 1994
Chemical Energetics & Thermochemistry
In a chemical reaction, the reacting species possess energy of motion known as
A
potential energy
B
free energy
C
bond energy
D
kinetic energy
E
hydration energy
medium Difficulty
Verified Correct Answer: Option D
Chemical Principles & Mechanism
No expanded working has been attached for this question yet. The verified answer is Option D.
Source: Myschool Past Questions Archive (Record #36357)
Chemistry
WAEC / WASSCE 1994
Stoichiometry, Mole Concept & Volumetric Analysis
The following compounds will decompose on heating except
A
NaHCO3
B
K2CO3
C
MgCO3
D
Ca(HCO3)2
E
ZnCO3
medium Difficulty
Verified Correct Answer: Option B
Chemical Principles & Mechanism
No expanded working has been attached for this question yet. The verified answer is Option B.
Source: Myschool Past Questions Archive (Record #36360)
Chemistry
WAEC / WASSCE 1994
Periodic Table & Periodicity
Solution
Which of the following reactions is accompanied by the first ionization energy of an element X?
A
X +(aq) → X 2+ (aq) + e-
B
X - (g) → X(g) + e-
C
X+ (g) → X2+ +e-
D
X (g) → X+ (g) +e-
E
X(s) → X + (g) + e-
medium Difficulty
Verified Correct Answer: Option D
Chemical Principles & Mechanism
ionization energy (IE) is the minimum energy required to remove an isolated gaseous atom's most loosely bound electron. The first ionization energy is quantitatively expressed as
\(X_{(g)} + energy ⟶ X^+_{(g)} + e^−\)
where X is any atom or molecule, \(X^+\) is the resultant ion when an electron( \(e^−\)) was removed from the original atom.
Source: Myschool Past Questions Archive (Record #36365)
Chemistry
WAEC / WASSCE 1994
Oxidation, Reduction & Redox Reactions
What is the molar of hydrogen sulphide gas in the reaction H2SO4(aq) + 3H2S(g) → 4S(s) + 4H2O (l)n represented by the following equation?
A
Reducing agent
B
A bleaching agent
C
A dehydrating agent
D
A sulphonating agent
E
An oxidizing agent
medium Difficulty
Verified Correct Answer: Option A
Chemical Principles & Mechanism
No expanded working has been attached for this question yet. The verified answer is Option A.
Source: Myschool Past Questions Archive (Record #36369)
Chemistry
WAEC / WASSCE 1994
Organic Chemistry II: Functional Groups, Polymers & Biomolecules
Alkanols have unexpectedly high boiling points relative to their molar masses because of intermolecular
A
hydrogen bonding
B
metallic bonding
C
covalent bonding
D
ionic bonding
E
van der Waals' forces
medium Difficulty
Verified Correct Answer: Option A
Chemical Principles & Mechanism
No expanded working has been attached for this question yet. The verified answer is Option A.
Source: Myschool Past Questions Archive (Record #36370)
Chemistry
WAEC / WASSCE 1994
Organic Chemistry II: Functional Groups, Polymers & Biomolecules
Sodium chloride is used in the following processes except in the
A
treatment of polluted water
B
preservation of food
C
separation of soap from glycerol
D
manufacture of chlorine
E
manufacture of caustic soda
medium Difficulty
Verified Correct Answer: Option A
Chemical Principles & Mechanism
No expanded working has been attached for this question yet. The verified answer is Option A.
Source: Myschool Past Questions Archive (Record #36371)
Chemistry
WAEC / WASSCE 1994
Nature of Matter & Separation Techniques
When naphthalene on heating changes from the solid state directly to the gaseous state it undergoes
A
evaporation
B
sublimation
C
decomposition
D
combustion
E
ionisation
medium Difficulty
Verified Correct Answer: Option B
Chemical Principles & Mechanism
No expanded working has been attached for this question yet. The verified answer is Option B.
Source: Myschool Past Questions Archive (Record #36345)
Chemistry
WAEC / WASSCE 1994
Electrolysis & Electrochemical Cells
Which of the following occurs when an aqueous solution of sodium hydroxide is electrolysed using graphite electrodes?
A
Sodium metal is produced at the anode
B
Sodium amalgam is formed at the cathode
C
Oxygen gas is produced at the anode
D
The grahite anode dissolves
E
The resulting solution becomes acidic
medium Difficulty
Verified Correct Answer: Option C
Chemical Principles & Mechanism
No expanded working has been attached for this question yet. The verified answer is Option C.
Source: Myschool Past Questions Archive (Record #36346)
Chemistry
WAEC / WASSCE 1994
Stoichiometry, Mole Concept & Volumetric Analysis
If the volume of a given mass of gas at 0oC is 27.3cm3, what will be the volume of the gas at 10oC, pressure remaining constant?
A
2.73cm3
B
28.3cm3
C
37.3cm3
D
273cm3
E
283cm3
medium Difficulty
Verified Correct Answer: Option B
Chemical Principles & Mechanism
No expanded working has been attached for this question yet. The verified answer is Option B.
Source: Myschool Past Questions Archive (Record #36347)