Which of the following scientists discovered the neutron?
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(C)
James Chadwick
2
How many protons does 4020Ca contain?
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(A)
20
3
If 100 atoms of element X contains 70 atoms of 9X and 30 atoms of 11X, calculate the relative atomic mass of X
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(A)
9.6
4
Consider the reaction represented by the equation: 23892U + 10 → 13956Ba + 9436Kr + 310n. The reaction represents a
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(A)
nuclear fission
5
How many orbitals are associated with the p-sub energy level?
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(B)
3
6
Which of the following elements has the electronic configuration:1s22s22p63s23p1? [11Na, 13A1, 14N,16S]
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(A)
Al
7
The following properties are characteristics of transition elements except
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(B)
fixed oxidation states
8
Which of the following ions is isoelectronic with neon? [\(_3\)Li, \(_9\)F, \(_{10}\)Ne, \(_{17}\)CI,\(_{19}\)K ]
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(B)
F-
9
Which of the following electronic configurations correctly represents an element in period 3 of the periodic table?
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(C)
1s2 2s2 2p6 3s2 3p4
10
An element Q forms a compound QCI5. In which group of the periodic table is Q?
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(C)
V
11
Which of the statements about the behaviour of the atom is correct?
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(D)
cations are smaller than the parent atom
12
Which of the following properties of covalent compounds is not correct? They
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(D)
have high boiling points
13
Which of the following arrangements is in order of increasing ionization energy?
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(A)
AI, Si, P, S
14
In bonded atoms, increase in electronegativity difference,
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(A)
increases polarity
15
Which of the following molecules is not linear in shape?
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(C)
NH3
16
The number of particles in one mole of a chemical compound is the
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(B)
avogadro's number
17
How many molecules are there in 14 g of nitrogen at s.t.p.? [N = 14, Avogadro's constant = 6.02 x 10\(^{23}\) mol-1]
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(B)
3.01 x 1023
18
Consider the reaction represented by the equation: 2NaHCO3 → Na2CO 3 + H 2O + CO 2. What is the mass of sodium trioxocarbonate (lV) produced by the complete decomposition of 33.6 g of sodium hydrogen trioxocarbonate (IV)? [NaHCO3 = 84, Na2CO3 = 106]
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(C)
21.2 g
19
What is the percentage by weight of calcium in Ca(OCI)2? [Ca = 40, Cl = 35.5, O = 16]
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(A)
28.0%
20
What is the value of -14oC on the Kelvin temperature scale?
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(A)
259K
21
Which of the following expressions correctly represents Charles' law?
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(D)
V = KT
22
In a mixture of gases which do not react chemically together, the pressure exerted by the individual gases is called
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(B)
partial pressure
23
In a chemical reaction, ∆H is positive when
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(A)
H (product) >H (reactant)
24
Consider the reaction represented by the following equation: H 2(g) + \(\frac{1}{2}\) O(g) → H 2O(g) ∆H =-285.8 KJmo -1 ∆H represents the enthalpy of
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(A)
formation
25
Salts that contain water of crystallization are said to be
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(D)
hydrated
26
Which of the following dilute acids does not react with metals to liberate hydrogen?
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(D)
HNO3(aq)
27
Which of the following compounds is not a double salt?
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(A)
Zn(OH)NO3
28
Which of the following hydroxides will readily dissolved in water?
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(B)
NaOH
29
Which of the following acids from normal salt only?
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(C)
Trioxonitrate (V) acid
30
A solution that contains as much solute as it can dissolve at a given temperature is said to be
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(B)
saturated
31
Which of the following salts is insoluble in water?
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(D)
AgCI.
32
Which of the following statement is correct? The solubility of
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(B)
gases decreases with increase in temperature
33
A catalyst increases the rate of chemical reaction by
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(B)
decreasing the activation energy of the reaction
34
Which of the following factors will affect the rate of the reaction represented by the equation? 2HCI(aq) + CaCO 3(s) → CaCI2(aq) + H2O (I) + CO2(g) l. Pressure ll. Concentration III. Nature of reactants IV. Temperature
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(B)
ll, lll and IV only
35
Which of the following substances is the anode in the dry Leclanche cell ?
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(D)
Zinc container
36
Consider the reaction represented by the equation: 2H2SO 4(aq0 + C(s) → 2H2O(l) + 2SO2(g) + CO 2(g) H2SO 4 is acting as
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(B)
an oxidizing agent
37
Which of the following oxides of nitrogen has oxidation number of + 1?
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(B)
N2O
38
The separation of petroleum fractions depends on the differences in their
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(A)
boiling points
39
Which of the following raw materials is used in the plastic industry ?
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(B)
Ethene
40
The product of the reaction between C 2H5OH and concentrated H2SO 4 at 170oC is
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(D)
CH2 = CH 2
41
When protein is heated to a high temperature it undergoes
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(B)
denaturation
42
What is the molecular formula of a compound with empirical CH2O and vapour density of 90? [H = 1, C = 12, O = 16]
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(D)
C6H12O6
43
What is the product of the reaction between propene and 1 mole of hydrogen iodide?
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(A)
CH3CHICH3
44
Ethanol reacts with excess acidified K2Cr 2O7 to produce
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(C)
ethanoic acid
45
Dry hydrogen chloride when dissolved in methylbenzene
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(C)
does not affect litmus paper
46
A consequence of global warming is
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(B)
flooding
47
The major product in the solvay process is
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(B)
Na 2CO 3
48
Which of the following alloys does not contain copper? l. Brass II. Bronze III. Steel
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(C)
lll only
49
The electron configuration of carbon atom in its excited state is [ 6C]
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(D)
1s 22s12px12py12pz1
50
The electron configuration of carbon atom in its excited state is [ 6C]
