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