WAEC - Chemistry (1995)

1
If a solid has a low melting point and dissolves readily in benzene, it would probably
Answer
(D)
have covalent bonding
2
Which of the following molecules is linear in shape?
Answer
(E)
CI2
3
Which of the following cannot be deduced from the electronic configuration of a transition metal?
Answer
(A)
Possession of magnetic property
4
What is the percentage by mass of copper in copper in copper (l) oxide (CU2O)? [O = 16; CU =64]
Answer
(A)
88.9%
5
A weak acid is one which
Answer
(B)
is slightly ionized in water
6
Which of the following species is always present in acidified water?
Answer
(D)
H3O+
7
The most suitable method for preparing lead (ll) chloride is by
Answer
(E)
mixing aqueous solutions Pb(NO3)2 and NaCI.
8
A positive brown ring test indicates the presence of
Answer
(A)
NO 3
9
Consider the reaction represented by the equation below: XO + YO → X + YO2 In the reaction, YO acts as
Answer
(C)
a reducing agent
10
Alums are classified as
Answer
(D)
double salts
11
Sodium chloride cannot conduct electricity in the solid state because it
Answer
(E)
does not contain mobile ions
12
What mass of copper will be deposited by the liberation of Cu2+ when 0.1F of electricity flows through an aqueous solution of a copper (ll) salt? [Cu = 64]
Answer
(E)
3.2g
13
What mass of copper will be deposited by the liberation of Cu2+ when 0.1F of electricity flows through an aqueous solution of a copper (ll) salt? [Cu = 64]
Answer
(E)
3.2g
14
Which of the following is not correct of the reaction represented by the equation below? 2C(s) + O2(g) → 2CO(g); ∆H = - xKJ
Answer
(C)
Carbon (lV) oxide is produced
15
H3O+(aq) + OH-(aq) → 2H2O(l). The heat change accompanying the process represented by the equation above is the heat of
Answer
(A)
neutralization
16
The following statements about graphite are correct except that it
Answer
(B)
has a network structure
17
Which of the following is hydrocarbons is unsaturated?
Answer
(B)
Benzene
18
The following can be obtained directly from the destructive distillation of coal except
Answer
(C)
producer gas
19
Fructose and glucose are classified as carbohydrates because they
Answer
(E)
conform to the general formula Cx(H2O)y
20
The gas produced when a mixture of sodium propanoate and soda lime is heated is
Answer
(C)
ethane
21
In which of the following processes are larger molecules broken down into smaller molecules?
Answer
(C)
Hydrolysis of starch
22
The following alkanols will yield alkanoic acids on reacting with excess acidified K2Cr2O7 except
Answer
(D)
(CH3)3COH
23
Which of the following is an alloy of mercury?
Answer
(D)
Amalgam
24
The function of limestone in the extraction of iron in the blast furnace is
Answer
(A)
removal of the earthly impurities
25
Metals which react with steam only when they are red-hot include
Answer
(E)
iron