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