The existance of two or more forms of the same element in the same physical state is known as
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(A)
allotropy
2
When an atom gains an electron, it becomes
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(B)
negatively charged
3
The alkali metals exhibit similar chemical properties because
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(B)
they have the same number of vallence electrons
4
What is the likely formula of compound formed between element M in group two and element X in group seven?
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(D)
MX2
5
''Equal volumes of all gases at the same temperature and pressure contain the same number of molecules'' is an expression of
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(C)
Avogadro's Law
6
What volume of carbon (lV) oxide is produced at s.t.p. when 2.5g of CaCO3 reacts with excess acid according to the following equation? CaCO3 + 2HCI → CaCI2 +H2O + CO2 [CaCO3 = 100; molar volume of a gas at s.t.p = 22.4dm3]
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(D)
0.56dm3
7
A solution of pH 7 is
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(B)
neutral
8
Which of the following equations represents a neutralization reaction?
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(C)
H2SO4 + KOH → KHSO4 + H2 O
9
Amphoteric oxides are oxides which
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(D)
react with acids alkalis
10
The following acids are monobasic except
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(D)
tetraoxophosphorus (V) acid
11
An arrangement of two different metals in aqueous solutions of their salts to produce an electronic current is known as
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(A)
electrochemical cell
12
In which of the following compounds is the oxidation number of nitrogen equal to + 3?
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(D)
HNO2
13
Which of the following statements is not correct about electrolysis?
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(A)
Reduction occurs at the anode
14
Which of the following is not correct about a catalyst? It
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(C)
can start a chemical rection which will normally not take place
15
The rate of production of hydrogen gas from the reaction between zinc granules and hydrochloric acid can be increased by
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(B)
using zinc powder instead of zinc granules
16
What does X represent in the following equation? H 2(g) + 1/2O2(g) → H2O (l); ∆H = xKJ.
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(E)
Enthalpy of formation
17
If the third member of a homologous series is C3H8, the fifth member will be
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(E)
C5H12
18
Which of the following exhibits resonance?
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(A)
Benzene
19
On exposing palm wine to air for some days, it becomes sour owing to the conversion of
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(C)
ethanol to ethanoic acid
20
When acidified KMnO4 solution is decolorised by ethene, the gas acts as
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(C)
a reducing agent
21
What amount of hydrogen will be required for complete hydrogenation of one mole of pent-3-yne?
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(B)
2 moles
22
When excess carbon (lV) oxide is passed into lime water, the turbidity produced initially disappears due to the formation of
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(C)
calcium hydrogentrioxocarbonate (IV)
23
Which of the following is a disaccharide?
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(D)
sucrose
24
Use this following information to answer this question. Compound X was boiled with concentrated hydrochloric acid for a long time. One of the products was found to be a sugar. Compound X was probably
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(D)
cellulose
25
Use this following information to answer this question. Compound X was boiled with concentrated hydrochloric acid for a long time. One of the products was found to be a sugar. What type of reaction was involved between compound X and concentrated hydrochloric acid?
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(C)
Hydrolysis
26
The component of air that can be removed by alkaline pyrogallol solution is
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(A)
oxygen
27
During water treatment for town supply, water is passed through layers of send beds in order to
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(B)
filter the water
28
The cleansing action of soap in hard water is not satisfactory because soap
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(A)
forms insoluble calcium and magnesium salts
29
What is the role of MnO2 in the reaction represented by the following equation?MnO2 + 4HCI2 + CI2 + 2H2O
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(B)
Oxidizing agent
30
Nitrogen is prepared on a large scale by the
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(A)
fractional distillation of liquefied air
31
Ammonia gas is suitable for performing the 'Fountain' experiment because the gas is
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(E)
very soluble in water
32
Which of the following metals will be the most suitable for use where lightness and resistance to corrosion are of importance?
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(E)
Aluminium
33
What amount of copper is deposited when 13.0g of zinc reacts with excess copper (ll) tetraoxosulphate (IV) solution according to the following equation? Zn (s) + CuSO4(aq) → ZnSO4(aq) + Cu (s) [Cu =63,5, Zn = 65]
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(B)
0.2mole
34
The products formed when sodium hydrogen trioxocarbonate (IV) is heated strongly are
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(E)
sodium trioxocarbonate (IV) carbon (IV) oxide and steam
35
The following are properties of transition metals except
