How many moles of oxygen molecules would be produced from the decomposition of 2.50 moles of potassium trioxochlorate (V)?
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(C)
3.75
4
For iodine crystals to sublime on heating, the molecules must acquire energy that is?
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(D)
greater than the forces of attraction in both the solid and the liquid phases
5
An element, E, has the electronic configuration 1s22s22p63s2p3. The reaction of E with a halogen X can give?
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(A)
EX3 and EX5
6
Two atoms represented as U and U are?
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(C)
isotopes
7
As the difference in electronegativity between bonded atoms increases, polarity of the bond?
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(B)
increases
8
Which group of elements forms hydrides that are pyramidal in structure?
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(C)
V
9
Water has a rather high boiling point despite its low molecular mass because of the presence of?
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(A)
hydrogen bonding
10
Argon is used in gas-filled electric lamp because it helps to?
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(B)
prevent oxidation of the lamp fillaments
11
The air around a petroleum refinery is most likely to contain?
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(C)
SO2, CO and NO2
12
Water can be identified by the use of?
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(A)
anhydrous copper (II) tetraoxosulphate (VI)
13
The phenomenon whereby sodium trioxocarbonate (IV) decahydrate loses some of its water of crystallization on exposure to the atmosphere is known as?
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(D)
efflorescence
14
A student prepares 0.5 M solution each of hydrochloric and ethanoic acids and then measured pH. The result would show that the?
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(D)
ethanoic acid solution has a higher pH
15
NH\(_3\) + H\(_3\)O\(^+\) → NH\(_4\)\(^+\) + H\(_2\)O. It may be deduced from the reaction above that?
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(C)
H3O+ acts as an acid
16
4.0 g of sodium hydroxide in 250 cm3 of solution contains?
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(A)
0.40 moles per dm3
17
During the electrolysis of a salt of a metal M, a current of 0.5 A flows from for 32 minutes 10 seconds and deposits 0.325 g of M, What is the charge of the metal ion?
(M = 65, If = 96,500 C per mole of electron)
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(B)
2
18
Which of the reactions occurs at the anode during the electrolysis of a very dilute aqueous solution of sodium chloride?
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(A)
OH- - e → OH
19
The oxidation states of chlorine in HOCL, HCLO3 and HCLO4 are respectively?
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(D)
+1, +5 and +7
20
A reaction takes places spontaneously if?
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(C)
∆H < T ∆S
21
The standard enthalpies of formation of CO2(g), H2O(g) and CO(g) in kJ mol- are -394, -242 and -110 respectively. What is the standard enthalpy change for the reaction CO(g) + H2(g)O → CO2(g) + H2(g)?
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(A)
-42 KJ mol-
22
10g of a solid is in equilibrium with its own vapour.
When 1 g of a small amount of solid is added, the vapour pressure?
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(A)
remains the same
23
NaCI(s) + H2SO4(I) → HCI(g) + NaHSO4(s).
In the reaction above, H2SO4 behaves as?
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(A)
a strong acid
24
Which of these gases can be dried with concentrated H2SO4?
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(D)
SO2
25
Which of these salts will produce its metal, oxygen and nitrogen (IV) oxide on heating?
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(A)
Silver and trioxonitrate (V)
26
An experiment produces a gaseous mixtures of carbon (IV) oxide and carbon (II) oxide. In order to obtain pure carbon (II) oxide, the gas mixture should be?
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(C)
bubbled through sodium hydroxide solution
27
Which of the following is a property of ionic chlorides?
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(B)
They react with aqueous AgNO3 to give a white precipiate which is soluble in excess ammonia
28
When dilute aqueous solutions of lead (II) nitrate and potassium bromide are mixed, a precipitate is observed.
The products of this reaction are?
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(D)
PbBr2(s) + K(aq) + K+(aq) + NO3(aq)
29
Bronze is an alloy of?
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(E)
copper and tin
30
The active reducing agent in the blast furnace for the extraction of iron is?
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(C)
carbon(II)oxide
31
The fraction of crude oil used as jet fuel is?
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(C)
kerosene
32
It is not desirable to use lead tetraethyl as an anti-knock agent because?
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(B)
of pollution effects from the exhaust fumes
33
Al2O3(s) + 3H2SO4(aq) → Al2(SO4(aq)) + 3H2(I)O
Al2O3(s) + 2NaOH(aq)) + 3H2(I)O → 2NaAl(OH)4(aq)).
We can conclude from the equations above that Al2O3(s) is?
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(B)
an amphoteric oxide
34
The carbon atoms on ethane are?
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(B)
sp3 hybridized
35
Palm wine turns sour with time because?
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(D)
microbial activity results in the production of orgain acids within it
36
Catalytic hydrogenation of benzene produces?
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(C)
cyclohexane
37
Which of the following represents saponification?
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(D)
Reaction of alkanoates with sodium hydroxide
38
The confirmatory test for alkanoic acids in organic qualitative analysis is the?
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(B)
reaction with alkanols to form esters
39
A gas that will turn orange potassium heptaoxodichromate (lV) solution to clear green is?
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(C)
sulphide (lV) oxide
40
Which of the curves above represents the behaviour of 1 mole of an ideal gas?
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(C)
lll
41
For which salt in the graph above does the solubility increase most rapidly with rise in temperature?
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(B)
KNO3
42
Half-cell reaction. From the data above , it can be deduced that the most powerful reducing agent of the four metals is
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(C)
Ba
43
In the diagram above, curve X represents the energy profile for a homogeneous gaseous reaction. Which of the following conditions would produce curve Y for the same reaction?
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(C)
Addition of a catalyst
44
The two functional groups in the above compound are
