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Chemistry
WAEC / WASSCE 2015
Atomic Structure, Orbitals & Nuclear Chemistry
The negatively charged particle in an atom is the
A
Electron
B
Neutron
C
Positron
D
Proton
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 #45736)
Chemistry
WAEC / WASSCE 2015
Atomic Structure, Orbitals & Nuclear Chemistry
How many orbits are contained in an atom with atomic number 13?
A
7
B
6
C
5
D
3
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 #45737)
Chemistry
WAEC / WASSCE 2015
Chemical Bonding & Intermolecular Forces
The Van der waals' forces are dominant intermolecular forces in_______?
A
Ammonium chloride
B
Chlorine
C
Sodium chloride
D
Water
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 #45738)
Chemistry
WAEC / WASSCE 2015
Stoichiometry, Mole Concept & Volumetric Analysis
The compound formed between 14X and 16Y is _______?
A
XY
B
XY2
C
X2Y
D
X4Y6
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 #45739)
Chemistry
WAEC / WASSCE 2015
Chemical Bonding & Intermolecular Forces
The shape of a molecule of water is _______?
A
Non-linear
B
Octahedral
C
Pyramidal
D
Tetrahedral
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 #45740)
Chemistry
WAEC / WASSCE 2015
Atomic Structure, Orbitals & Nuclear Chemistry
Solution
A metallic ion Z\(^{2+}\) with an inert gas structure contains 18 electrons. How many protons are contained in this ion?
A
20
B
18
C
16
D
2
medium Difficulty
Verified Correct Answer: Option A
Chemical Principles & Mechanism
The number of electron would have been equal to number of proton if the atom were a neutral atom or represented as Z without Z\(^{2+}\). But because it is Z\(^{2+}\), carrying +2, meaning 2electrons were given out, therefore number of protons will be more than number electron by 2. i.e number of electron + 2 = 18 + 2 = 20. Therefore, the number of protons will be 20.
Source: Myschool Past Questions Archive (Record #45742)
Chemistry
WAEC / WASSCE 2015
Organic Chemistry I: Hydrocarbons & Crude Oil
Solution
Which of the following pairs of compounds belongs to the same homologous series?
A
C3H8 and C3H6
B
C4H10 and C5H10
C
C2H4 and C4H10
D
C2H6 and C4H10
medium Difficulty
Verified Correct Answer: Option D
Chemical Principles & Mechanism
both ethane and butane are in the same homologous series.( alkanes)
Source: Myschool Past Questions Archive (Record #45744)
Chemistry
WAEC / WASSCE 2015
Metals, Transition Elements & Extraction
The following transition metal ions would be coloured in aqueous solution except________?
A
Cr3+
B
Fe3+
C
Mn3+
D
Sc3+
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 #45745)
Chemistry
WAEC / WASSCE 2015
Organic Chemistry II: Functional Groups, Polymers & Biomolecules
The gas given off when ethanol reacts with sodium is
A
Carbon(IV)oxide
B
Hydrogen
C
Methane
D
Oxygen
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 #45746)
Chemistry
WAEC / WASSCE 2015
Stoichiometry, Mole Concept & Volumetric Analysis
Which of the following halogens is solid at room temperature?
A
Bromine
B
Chlorine
C
Flourine
D
Iodine
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 #45747)
Chemistry
WAEC / WASSCE 2015
Periodic Table & Periodicity
The alkaline earth metals have similar chemical properties because________?
A
They are in the same period
B
Their salts are colourless
C
They have the same number of valence electrons
D
They are very reactive
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 #45748)
Chemistry
WAEC / WASSCE 2015
Atomic Structure, Orbitals & Nuclear Chemistry
The number of unpaired electrons in an atom of an element 8Q is _______?
A
2
B
4
C
6
D
8
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 #45749)
Chemistry
WAEC / WASSCE 2015
Chemical Bonding & Intermolecular Forces
The bond formed when ammonia reacts with hydrogen ion to form ammonium ion is
A
Covalent
B
Dative
C
Hydrogen bond
D
Ionic
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 #45750)
Chemistry
WAEC / WASSCE 2015
Periodic Table & Periodicity
Solution
To which group and period respectively does an element with 15 electrons belong?
A
3 and 3
B
3 and 5
C
5 and 3
D
5 and 5
medium Difficulty
Verified Correct Answer: Option C
Chemical Principles & Mechanism
An element with 15 electrons is Phosphorus (P), which belongs to Group 5 and Period 3, as its electron configuration ends in, showing 5 valence electrons in the third shell.
Source: Myschool Past Questions Archive (Record #45751)
Chemistry
WAEC / WASSCE 2015
Chemical Bonding & Intermolecular Forces
The shape of a graphite crystal is
A
Tetrahedral
B
Pyramidal
C
Octahedral
D
Hexagonal
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 #45752)