JEE MAIN - Chemistry (2002)

1
If an endothermic reaction is non-spontaneous at freezing point of water and becomes feasible at its boiling point, then :
Trả lời
(B)
$$\Delta H$$ and $$\Delta S$$ are both +ve
2
For the reactions
2C + O₂ $$\to$$ 2CO₂; $$\Delta H$$ = -393 J
2Zn + O₂ $$\to$$ 2ZnO; $$\Delta H$$ = -412 J
Trả lời
(D)
Zn can oxidise carbon
3
The heat required to raise the temperature of body by 1 K is called :
Trả lời
(B)
thermal capacity
4
A heat engine absorbs heat Q₁ at temperature T₁ and heat Q₂ at temperature T₂. Work done by the engine is J (Q₁ + Q₂). This data :
Trả lời
(A)
violates 1^st law of thermodynamics
5
1 M NaCL and 1 M HCL are present in an aqueous solution. The solution is
Trả lời
(A)
not a buffer solution with pH < 7
6
Let the solubility of an aqueous solution of Mg(OH)₂ be x then its K_sp is :
Trả lời
(A)
4x³
7
Species acting as both Bronsted acid and base is :
Trả lời
(A)
(HSO₄)^-1
8
Change in volume of the system does not alter which of the following equilibria?
Trả lời
(A)
N₂(g) + O₂(g) $$\leftrightharpoons$$ 2NO (g)
9
For the reaction CO (g) + (1/2) O₂ (g) $$\leftrightharpoons$$ CO₂ (g), K_p/K_c is :
Trả lời
(C)
(RT)^-1/2
10
A similarity between optical and geometrical isomerism is that
Trả lời
(C)
both are included in stereoisomerism
11
The functional group, which is found in amino acid is
Trả lời
(D)
both (a) and (b)
12
Which of the following does not show geometrical isomerism?
Trả lời
(C)
1,1-dichloro-1-pentene
13
Arrangement of (CH₃)₃C-, (CH₃)₂CH-, CH₃-CH₂- when attached to benzyl or an unsaturated group in increasing order of inductive effect is
Trả lời
(B)
CH₃-CH₂- < (CH₃)₂CH- < (CH₃)₃C-
14
In which of the following species is the underlined carbon having sp³ hybridisation?
Trả lời
(B)
15
The reaction :
$${(CH)_3}C - Br\buildrel {{H_2}O} \over \longrightarrow {(CH)_3}C - OH$$
Trả lời
(B)
substitution reaction
16
Racemic mixture is formed by mixing two
Trả lời
(B)
enantiomers with chiral compounds
17
Which of these will not react with acetylene ?
Trả lời
(A)
NaOH
18
What is the product when acetylene reacts with hypochlorous acid ?
Trả lời
(C)
Cl₂CHCHO
19
In a mixture of A and B, components show negative deviation when :
Trả lời
(D)
A - B interaction is stronger than A - A and B - B interaction
20
Freezing point of an aqueous solution is (-0.186)^oC. Elevation of boiling point of the same solution is K_b = 0.512 ^oC, K_f = 1.86 ^oC, find the increase in boiling point.
Trả lời
(B)
0.0512 ^oC
21
RNA is different from DNA because RNA contains
Trả lời
(B)
ribose sugar and uracil
22
How do we differentiate between Fe³⁺ and Cr³⁺ in group III?
Trả lời
(B)
by increasing $$NH_4^+$$ ion concentration
23
When primary amine reacts with chloroform in ethanoic KOH then the product is
Trả lời
(A)
an isocyanide
24
Which of the following compounds has wrong $$IUPAC$$ name ?
Trả lời
(C)
25
Following types of compounds (as $$I, II$$ )

are studied in terms of isomerism in :
Trả lời
(D)
stereoisomerism
26
The correct order of ionic radius is
Trả lời
(A)
$$Ce > Sm > Tb > Lu$$
27
$$C{e^{ + 3}},\,\,L{a^{ + 3}},\,\,P{m^{ + 3}}\,\,$$ and $$Y{b^{ + 3}}\,\,$$ have ionic radial in the increasing order as
Trả lời
(B)
$$Y{b^{ + 3}}\,\, < P{m^{ + 3}}\,\, < C{e^{ + 3}}\,<\,L{a^{ + 3}}$$
28
Trả lời
(B)
29
Picric acid is :
Trả lời
(C)
30
The type isomerism present in nitropentammine chromium $$\left( {{\rm I}{\rm I}{\rm I}} \right)$$ chloride is :
Trả lời
(B)
linkage
31
Conductivity (Seimen’s S) is directly proportional to area of the vessel and the concentration of the solution in it and is inversely proportional to the length of the vessel then, then constant of proportionality is expressed in :
Trả lời
(B)
Sm² mol^-1
32
For the following cell with hydrogen electrodes at two different pressure p₁ and p₂. What will be the emf for the given cell :

$$\eqalign{ & Pt({H_2})|{H^ + }(aq)|Pt({H_2}) \cr & \,\,\,\,\,{p_1}\,\,\,\,\,\,\,\,\,\,\,\,\,\,1M\,\,\,\,\,\,\,\,\,\,\,\,{p_2} \cr} $$
Trả lời
(B)
$${{RT} \over 2F}{\log _e}{{{P_1}} \over {{P_2}}}$$
33
EMF of a cell in terms of reduction potential of its left and right electrodes is :
Trả lời
(C)
E = E_right - E_left
34
Which of the following reaction is possible at anode?
Trả lời
(A)
2Cr³⁺ + 7H₂O $$\to Cr_2O_7^{2-}$$ + 14H⁺
35
When the sample of copper with zinc impurity is to be purified by electrolysis, the appropriate electrodes are :
Trả lời
(D)
cathode = pure copper, anode = impure sample
36
Which of the following is a redox reaction ?
Trả lời
(D)
Zn + 2AgCN $$\to$$ 2Ag+ Zn(CN)₂
37
Units of rate constant of first and zero order reactions in terms of molarity M unit are respectively
Trả lời
(A)
sec^-1, Msec^-1
38
For the reaction A + 2B $$\to$$ C, rate is given by R = [A] [B]² then the order of the reaction is
Trả lời
(A)
3
39
The differential rate law for the reaction H₂ + I₂ $$\to$$ 2HI is
Trả lời
(D)
$$ - 2{{d\left[ {{H_2}} \right]} \over {dt}}$$ = $$ - 2{{d\left[ {{I_2}} \right]} \over {dt}}$$ = $${{d\left[ {{HI}} \right]} \over {dt}}$$
40
If half-life of a substance is 5 yrs, then the total amount of substance left after 15 years, when initial amount is 64 grams is
Trả lời
(D)
8 grams
41
$$\beta$$ - particle is emitted in radioactivity by
Trả lời
(C)
conversion of neutron to proton
42
The integrated rate equation is Rt = log C₀ - log C_t . The straight line graph is obtained by plotting
Trả lời
(A)
time vs log C_t
43
Which of the following statements is true?
Trả lời
(C)
chemical bond formation takes place when forces of attraction overcome the forces of repulsion
44
Oxidation number of Cl in CaOCl₂ (bleaching powder) is :
Trả lời
(D)
+1 and -1 since it contains ClO^- and Cl^-
45
When KMnO₄ acts as an oxidising agent and ultimately forms [MnO₄]^-2, MnO₂, Mn₂O₃, Mn⁺² then the number of electrons transferred in each case respectively is :
Trả lời
(C)
1, 3, 4, 5
46
Which of the following ions has the maximum magnetic moment?
Trả lời
(A)
Mn²⁺
47
Most common oxidation states of Ce (cerium) are :
Trả lời
(A)
+3, +4
48
A square planar complex is formed by hybridisation of which atomic orbitals ?
Trả lời
(B)
s, p_x, p_y, d_{x² - y²}
49
The most stable ion is :
Trả lời
(C)
[Fe(CN)₆]^3-
50
CH₃ - Mg - Br is an organometallic compound due to :
Trả lời
(B)
C - Mg bond
51

What is B?
Trả lời
(C)
CH₂ = CHCOOH
52
With increase of temperature, which of these changes?
Trả lời
(C)
molarity
53
In a compound C, H and N atoms are present in 9 : 1 : 3.5 by weight . Molecular weight of the compound is 108 g mol^-1 . Molecular formula of compound is
Trả lời
(C)
C₆H₈N₂
54
Number of atoms in 558.5 gram Fe (at. wt. of Fe = 55.85 g mol^-1) is
Trả lời
(A)
twice that in 60 g carbon
55
Uncertainty in position of a minute particle of mass 25 g in space is 10^-5 m. What is the uncertainty in its velocity (in ms^-1) (h = 6.6 $$\times$$ 10^-34 Js)
Trả lời
(C)
2.1 $$\times$$ 10^-28
56
In a hydrogen atom, if energy of an electron in ground state is -13.6 eV, then that in the 2^nd excited state is
Trả lời
(A)
-1.51 eV
57
In which of the following species the interatomic bond angle is 109^o28' ?
Trả lời
(B)
NH₄⁺, BF₄^-
58
Hybridisation of underline atom changes in
Trả lời
(A)
$$\underline {Al} {H_3}$$ changes to $$AlH_4^-$$
59
Which of the following are arranged in an increasing order of their bond strengths?
Trả lời
(B)
$$O_2^{2-}$$ < $$O_2^-$$ < $$O_2$$ < $$O_2^{+}$$
60
Acetylene does not react with :
Trả lời
(D)
$\mathrm{NaOH}$
61
For a cell given below

$$ \begin{aligned} \mathrm{Ag}^{+}+\mathrm{e}^{-} & \longrightarrow \mathrm{Ag}; E^{\circ}=x \\\\ \mathrm{Cu}^{2+}+2 e^{-} & \longrightarrow \mathrm{Cu}{;} E^{\circ}=y \end{aligned} $$

$$ E^{\circ} \text { cell is } $$ :
Trả lời
(C)
$y-x$