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Chemistry
WAEC / WASSCE 2015
Matter & Separation Techniques
The vapour pressure of a liquid depends on:
I. Temperature II. rate of condensation III. Cohesive forces holding the particles together.
A
I
B
I and II
C
I and III
D
II and III
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 #45769)
Chemistry
WAEC / WASSCE 2015
Matter & Separation Techniques
Which of the following gases will diffuse most rapidly?
[H = 1.00, C = 12.0, O = 16.0, S = 32.0, Cl = 35.5]
A
Cl2
B
SO2
C
CH4
D
C2H6
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 #45771)
Chemistry
WAEC / WASSCE 2015
Kinetics, Energetics and Equilibrium
Solution
When a reaction is endothermic,
A
Enthalpy change, \(\Delta\)H is negative
B
Heat content of a product is less than the heat content of a reactant
C
Heat content of reactants is less than the heat content of product
D
The reaction is non-spontaneous
medium Difficulty
Verified Correct Answer: Option C
Chemical Principles & Mechanism
An endothermic reaction is any chemical reaction that absorbs heat from its environment. The absorbed energy provides the activation energy for the reaction to occur.
Source: Myschool Past Questions Archive (Record #45773)
Chemistry
WAEC / WASSCE 2015
Acids, Bases, and Salts
Solution
An example of an acid salt is
A
CH3COOONa
B
Mg(OH)Cl
C
NaHSO4
D
(NH4)2SO4
medium Difficulty
Verified Correct Answer: Option C
Chemical Principles & Mechanism
Acidic Salt: A normal salt which is formed by the neutralization of a strong acid and weak base is called acidic salt
Source: Myschool Past Questions Archive (Record #45779)
Chemistry
WAEC / WASSCE 2015
Electrochemistry and Redox
Solution
Which of the following oxides can be reduced by hydrogen?
A
Aluminium oxide
B
Magnesium oxide
C
Sodium oxide
D
Silver oxide
medium Difficulty
Verified Correct Answer: Option D
Chemical Principles & Mechanism
Considering the electrochemical series, we can say that hydrogen can reduce only oxides of copper, mercury, silver, and gold as these metals are less reactive than hydrogen. The reduction of oxides of tin, iron, zinc, magnesium, calcium, and potassium is not possible by hydrogen as these metals are more reactive than hydrogen
Source: Myschool Past Questions Archive (Record #45780)
Chemistry
WAEC / WASSCE 2015
Matter & Separation Techniques
Solubility is practically applied in
A
Fractional distillation
B
The determination of pH
C
The determination of saturation in hydrocarbons
D
Solvent extraction
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 #45818)
Chemistry
WAEC / WASSCE 2015
Matter & Separation Techniques
Which of the following compounds is the least soluble in water?
A
CaCl2
B
CaSO4
C
NaCl
D
Na2SO4
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 #45819)
Chemistry
WAEC / WASSCE 2015
Matter & Separation Techniques
A substance which dissolves readily in organic solvent would
A
Be a covalent compound
B
Have strong electrostatic forces of attraction
C
have a high melting point
D
Conduct electricity in molten state
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 #45821)
Chemistry
WAEC / WASSCE 2015
Kinetics, Energetics and Equilibrium
A change in the temperature of a saturated solution disturbs the equilibrium between the
A
Undissolved solute and the solvent
B
Dissolved solute and the solvent
C
Dissolved solute and the undissolved solute
D
Dissolved solute and the solution
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 #45823)
Chemistry
WAEC / WASSCE 2015
Electrochemistry and Redox
Which of the following statements about an electrochemical cell is correct? Oxidation occurs
A
At the anode
B
At the cathode
C
Through the salt bridge
D
In the aqueous solution
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 #45824)
Chemistry
WAEC / WASSCE 2015
Matter & Separation Techniques
Consider the following reaction equation:
CuO(s) + H2(g) \(\to\) Cu(s) + H2O(1)
Which substance is oxidized?
A
Cu
B
CuO
C
H2
D
H2O
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 #45826)
Chemistry
WAEC / WASSCE 2015
Matter & Separation Techniques
Which of the following metals is the strongest reducing agent?
A
Sodium
B
Silver
C
Potassium
D
Copper
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 #45828)
Chemistry
WAEC / WASSCE 2015
Organic Chemistry
The complete hydrogenation of benzene gives
A
Cyclohexene
B
Cyclohexane
C
Hexene
D
Hexane
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 #45829)
Chemistry
WAEC / WASSCE 2015
Stoichiometry & Mole Concept
Solution
A compound has an empirical formular CH2O and molecular mass of 90.
[H = 1.00, C = 12.0, O = 16.0]
A
C4H10O2
B
C3H10O2
C
C3H6O3
D
C2H2O4
medium Difficulty
Verified Correct Answer: Option C
Chemical Principles & Mechanism
(CH2O)n = 90; (12 + (1 x 2) + 16)n = 90
(12 + 2 + 16)n = 90; 30n = 90; n = \(\frac{90}{30}\); n = 3
(CH2O)3 = Molecular formula ; = C3H6O3
Source: Myschool Past Questions Archive (Record #45831)
Chemistry
WAEC / WASSCE 2015
Matter & Separation Techniques
Which of the following reactions would take place when concentrated sodium hydroxide solution is added to palm oil?
A
Esterification
B
Neutralization
C
Polymerization
D
Saponification
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 #45833)