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Chemistry WAEC / WASSCE 2025 Acids, Bases, and Salts
Biotechnology is applied in the following processes except
A
baking of bread
B
production of wine
C
production of antibiotics
D
manufacturing of soap
medium Difficulty
Chemistry WAEC / WASSCE 2025 Stoichiometry & Mole Concept
The percentage by mass of water in Na\(_2\)CO\(_3\).10H\(_2\)O is [ Na\(_2\)CO\(_3\).10H\(_2\)O = 286, H\(_2\)O = 18 ]
A
68.4%
B
62.9%
C
9.7%
D
6.3%
medium Difficulty
Chemistry WAEC / WASSCE 2025 Acids, Bases, and Salts
Which of the following conditions are necessary for the preparation of alkanoates from alkanols and alkanoic acids?
A
Water and NaOH
B
Conc. H\(_2\)SO\(_4\) and heat
C
NaOH and heat
D
Water and aqueous HCl
medium Difficulty
Chemistry WAEC / WASSCE 2025 Atomic Structure and Periodic Table
All the following compounds are covalent except
A
NO\(_2\)
B
SO\(_3\)
C
SO\(_2\)
D
KNO\(_3\)
medium Difficulty
Chemistry WAEC / WASSCE 2025 Acids, Bases, and Salts
A salt that could be prepared by double decomposition is
A
sodium trioxocarbonate (IV)
B
barium trioxonitrate (V)
C
lead (II) trioxonitrate (V)
D
silver chloride
medium Difficulty
Chemistry WAEC / WASSCE 2025 Matter & Separation Techniques
The IUPAC name of the compound CH\(_3\)CHClCH\(_2\)OH is
A
chloropropanol
B
1-chloropropan-1-ol
C
2-chloropropan-3-ol
D
2-chloropropan-1-ol
medium Difficulty
Chemistry WAEC / WASSCE 2025 Atomic Structure and Periodic Table
Neutral atom of Neon with atomic number 10 is isoelectronic with
A
K\(^+\)
B
Mg\(^{2+}\)
C
Ca\(^{2+}\)
D
Li\(^+\)
medium Difficulty
Chemistry WAEC / WASSCE 2025 Atomic Structure and Periodic Table
Which of the following species is the most powerful reducing agent?
A
Bromine atom
B
Chlorine atom
C
Fluoride atom
D
Iodine atom
medium Difficulty
Chemistry WAEC / WASSCE 2025 Atomic Structure and Periodic Table
The electron configuration of element Y is 1S\(^2\)2S\(^2\)2P\(^6\)3S\(^2\)3P\(^4\). Y, therefore,
A
has mass number of 16
B
has three unpaired electron
C
belongs to period 4
D
belongs to group VI
medium Difficulty
Chemistry WAEC / WASSCE 2025 Atomic Structure and Periodic Table
Which of the following alkanols is tertiary?
A
2-methylpentan-2-ol
B
2-methylpentan-1-ol
C
pentan-3-ol
D
pentan-2-ol
medium Difficulty
Chemistry WAEC / WASSCE 2025 Acids, Bases, and Salts
Which of the following elements is commercially obtained by the electrolysis of its fused salt?
A
Silver
B
Copper
C
Helium
D
Sodium
medium Difficulty
Chemistry WAEC / WASSCE 2025 Atomic Structure and Periodic Table
The lustre of a metal is due to its
A
high density
B
refractive density
C
chemical inertness
D
free electrons
medium Difficulty
Chemistry WAEC / WASSCE 2025 Atomic Structure and Periodic Table
Exothermic reactions take place when energy given out in making bonds is
A
less than energy in for breaking bonds
B
more than energy taken in for breaking bonds
C
equal to the energy taken in for breaking bonds
D
remains the same as the energy taken in
medium Difficulty
Chemistry WAEC / WASSCE 2025 Acids, Bases, and Salts
Which of the following metals would not release hydrogen when reacted with dilute HCl?
A
Calcium
B
Silver
C
Iron
D
Zinc
medium Difficulty
Chemistry WAEC / WASSCE 2025 Atomic Structure and Periodic Table
Five d-orbitals have the same energy level in an isolated transition metal are described as
A
degenerate
B
non-degenerate
C
high level orbital
D
low-level orbital
medium Difficulty
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