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Chemistry
WAEC / WASSCE 1993
Nature of Matter & Separation Techniques
When the trioxonitrate (IV) salt of an alkali metal Y is heated, the formula of the residue is
A
Y2O
B
YNO2
C
Y2O3
D
Y (NO2)2
E
YO2
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 #36309)
Chemistry
WAEC / WASSCE 1993
Oxidation, Reduction & Redox Reactions
Which of the following compounds of tin is a strong reducing agent?
A
SnCI2
B
SnCI4
C
SnO2
D
SnH4
E
Sn(OH)2
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 #36310)
Chemistry
WAEC / WASSCE 1993
Water, Solutions & Solubility
In which of the following pairs are both substances deliquescent?
A
CaCI2 and H2SO4
B
NaOH and MgSO4 7H2O
C
CaCI2 and NaOH
D
CUO and NaCI
E
CaCO3 and MgCI2
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 #36311)
Chemistry
WAEC / WASSCE 1993
Non-Metals & Their Compounds
Producer gas is a mixture of
A
oxygen and hydrogen
B
Hydrogen and nitrogen
C
nitrogen and oxygen
D
nitrogen and carbon (ll) oxide
E
hydrogen and carbon (ll) oxide
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 #36312)
Chemistry
WAEC / WASSCE 1993
Organic Chemistry I: Hydrocarbons & Crude Oil
An alkene may be converted to an alkane by
A
halogenation
B
hydrolysis
C
dehydration
D
hydrogenation
E
decomposition
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 #36313)
Chemistry
WAEC / WASSCE 1993
Particulate Nature of Matter, Laws & Formulae
Which of the following gases are diatomic except
A
nitrogen
B
helium
C
hydrogen
D
fluorine
E
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 #36314)
Chemistry
WAEC / WASSCE 1993
Atomic Structure, Orbitals & Nuclear Chemistry
Which of the following is correct about the electrons in the 1s orbital? They
A
have the same spin
B
are easier to remove than those in the 2p orbital
C
are closest to the nucleus
D
have the same energy as those in the 2s orbital
E
have different magnetic quantum numbers
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 #36315)
Chemistry
WAEC / WASSCE 1993
Organic Chemistry II: Functional Groups, Polymers & Biomolecules
Solution
The product of the reaction between ethanol and excess acidified K\(_2\)Cr\(_2\)O\(_7\) is
A
ethanal
B
ethylethanoate
C
ethanoic acid
D
ethyne
E
ethanedioic acid
medium Difficulty
Verified Correct Answer: Option C
Chemical Principles & Mechanism
When ethanol reacts with excess acidified potassium dichromate (K₂Cr₂O₇), the product is ethanoic acid (acetic acid).
Acidified potassium dichromate is a strong oxidizing agent. It oxidizes ethanol (C₂H₅OH) to ethanoic acid (CH₃COOH).
Source: Myschool Past Questions Archive (Record #36316)
Chemistry
WAEC / WASSCE 1993
Nature of Matter & Separation Techniques
When ammonium chloride is dissolved in water in a test tube, the tube feels colder showing that
A
the solution is unsaturated
B
sublimation has ocurred
C
ammonia gas is evolved
D
the process is endothermic
E
condensation has occurred
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 #36317)
Chemistry
WAEC / WASSCE 1993
Stoichiometry, Mole Concept & Volumetric Analysis
Zinc displaces copper from an aqueous solution of copper (ll) salt because
A
copper is a transition element
B
copper is a moderately reactive metal
C
Zinc and copper have reducing prperties
D
zinc is more reactive than copper
E
zinc reacts with both acids and alkalis
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 #36319)
Chemistry
WAEC / WASSCE 1993
Metals, Transition Elements & Extraction
The alloy used for metal work and plumbing contains
A
lead and tin
B
iron and carbon
C
copper and tin
D
aluminium and copper
E
lead and antimony
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 #36320)
Chemistry
UTME / JAMB 1993
Organic Chemistry I: Hydrocarbons & Crude Oil
The fraction of crude oil used as jet fuel is
A
refinery gas
B
diesel oil
C
kerosine
D
gasoline
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 #44443)
Chemistry
UTME / JAMB 1993
Nature of Matter & Separation Techniques
Solution
The dissolution of common salt in water is a physical change because
A
the salt can be obtained by crystallization
B
the salt can be recovered by the evaporation of water
C
heat is not generated during mixing
D
the solution will not boil at 100oC
medium Difficulty
Verified Correct Answer: Option B
Chemical Principles & Mechanism
The evaporation of water is a physical change. When water evaporates, it changes from the liquid state to the gas state, but it is still water; it has not changed into any other substance.
Source: Myschool Past Questions Archive (Record #44441)
Chemistry
UTME / JAMB 1993
Stoichiometry, Mole Concept & Volumetric Analysis
Solution
At 25oC and 1atm, a gas occupies a volume of 1.50dm3. What volume will it occupy at 100oC and 1atm?
A
1.88 dm3
B
6.00 dm3
C
18.80 dm3
D
18.80 dm3
E
60.00dm3
medium Difficulty
Verified Correct Answer: Option A
Chemical Principles & Mechanism
\(\frac{v_1}{T_1} = \frac{V_2}{T_2}\)
V2 = \(\frac{V_1 \times T_2}{T_1}\)
= \(\frac{1.50 \times 373}{298}\)
= 1.88 dm3
Source: Myschool Past Questions Archive (Record #44442)
Chemistry
WAEC / WASSCE 1993
Organic Chemistry II: Functional Groups, Polymers & Biomolecules
Solution
(a) State one air pollution that causes:
(i) blood poisoning
(ii) acid poisoning
(iii) blackening of the walls of buildings
(b) Mention one major chemical industry in each case which requires the following as raw materials:
(i) petrochemicals;
(ii) cellulose.
medium Difficulty
Verified Correct Answer: Option
Chemical Principles & Mechanism
(i) Carbon(II) oxide prevents the oxygenation of the blood.
(ii) Sulphur(IV) oxide resolved in rain water ged in rain water in the atmosphere to give acid rain.
(iii) Hydrogen sulphide reacts with the lead content of the paint to give black stains of lead(II) sulphide (PbS\(_{(s)}\)).
(b)(i) Petrochemical industry
(ii) Brewery or Brewing industry.
Source: Myschool Past Questions Archive (Record #54437)