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Chemistry
WAEC / WASSCE 1999
Atomic Structure, Orbitals & Nuclear Chemistry
Calcium atom ionizes by
A
gaining two electrons
B
losing two electrons
C
sharing two electrons
D
gaining two protons
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 #36660)
Chemistry
WAEC / WASSCE 1999
Periodic Table & Periodicity
Which of the following properties increases down a group in the Periodic Table?
A
Atomic radius
B
Electronegativity
C
Electon affinity
D
Ionization energy
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 #36661)
Chemistry
WAEC / WASSCE 1999
Periodic Table & Periodicity
In the Periodic Table, the elements that loss electrons most readily belong to
A
Group 1 A
B
Group 11 A
C
Group 111 A
D
Group V11 A
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 #36662)
Chemistry
WAEC / WASSCE 1999
Stoichiometry, Mole Concept & Volumetric Analysis
Solution
Which of the following reactions is not feasible?
A
Cl2 + 2Kl → 2KCI + I2
B
Cl2 + 2NaF → 2NaCI + F2
C
Zn + CuCI2 → ZnCl2 + Cu
D
Zn + 2AgNO3 → Zn(NO3)2 + 2Ag
medium Difficulty
Verified Correct Answer: Option B
Chemical Principles & Mechanism
Option B - Cl\(_2\) + 2NaF → 2NaCI + F\(_2\) is not feasible. Meaning the reaction cannot take place.
Here is why:
The reaction implies Chlorine is more reactive than Fluorine, hence it can displace F from the NaF. This is not true because Fluorine is more reactive than Chlorine, hence a less reactive element like Chlorine cannot displace a more reactive element like Fluorine. Hence the reaction is not feasible ( not possible).
Source: Myschool Past Questions Archive (Record #36663)
Chemistry
WAEC / WASSCE 1999
Stoichiometry, Mole Concept & Volumetric Analysis
Which of the following halogens is the most reactive?
A
F2
B
Br2
C
l2
D
Cl
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 #36670)
Chemistry
WAEC / WASSCE 1999
Stoichiometry, Mole Concept & Volumetric Analysis
Which of the following atoms contains the highest number of electrons in the outermost shell?
A
8O
B
10Ne
C
15P
D
19K
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 #36655)
Chemistry
WAEC / WASSCE 1999
Atomic Structure, Orbitals & Nuclear Chemistry
What is the electronic configuration of an element represented as 199X?
A
1s 22s2 2p 5
B
1s22s23s23p3
C
1s2 2s2 2p 33s2
D
1s 22s22p 63s23p64s 1
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 #36656)
Chemistry
WAEC / WASSCE 1999
Atomic Structure, Orbitals & Nuclear Chemistry
Pauli Exclusion Principle is related to
A
quantum numbers of electrons
B
reversiblility of equlibrium reactions
C
electronegativity values of elements
D
collision theory of reaction rates
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 #36657)
Chemistry
WAEC / WASSCE 1999
Stoichiometry, Mole Concept & Volumetric Analysis
Which of the orbitals 4s, 4p, 4d and 4f has the lowest energy?
A
4f
B
4p
C
4d
D
4s
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 #36658)
Chemistry
WAEC / WASSCE 1999
Atomic Structure, Orbitals & Nuclear Chemistry
Two radioactive elements Q and S have half-life periods of 10 hours and 20 hours respectively. Therefore
A
S decays faster than Q
B
Q is twice as stable as S
C
Q emits fewer particles than S
D
S is more stable than Q
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 #36659)
Chemistry
WAEC / WASSCE 1999
Chemical Bonding & Intermolecular Forces
The crystal layers in graphite are held together by
A
electrostatic forces
B
van der Waals' forces
C
hydrogen bonds
D
covalent bonds
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 #36672)
Chemistry
WAEC / WASSCE 1999
Stoichiometry, Mole Concept & Volumetric Analysis
Which of the following compounds has the highest ionic character?
A
PCI5
B
SiCI4
C
AICI3
D
KCI
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 #36673)
Chemistry
WAEC / WASSCE 1999
Periodic Table & Periodicity
If an element with high electron affinity combines with another element with low ionization energy the bond formed will be mainly
A
covalent
B
ionic
C
dative
D
metallic
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 #36680)
Chemistry
WAEC / WASSCE 1999
Particulate Nature of Matter, Laws & Formulae
Solution
One mole of a compound M(HCO3)2 has a mass of 162g. Calculate the relative atomic mass of M. [H = 1, C =12, O = 16]
A
122
B
101
C
53
D
40
medium Difficulty
Verified Correct Answer: Option D
Chemical Principles & Mechanism
One of the mole of M(HCO3)2 = 162g; M +(1 + 12 + 16 x 3) x 2 = 162; M +122 = 162,:. M = 162 - 122 = 40g
Source: Myschool Past Questions Archive (Record #36683)
Chemistry
WAEC / WASSCE 1999
Stoichiometry, Mole Concept & Volumetric Analysis
Exhaust fumes discharged from a smoky vehicle gradually become invisible as a result of
A
diffusion
B
combustion
C
absorption
D
emission
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 #36693)