JEE MAIN - Chemistry (2004)

1
An ideal gas expands in volume from 1$$\times$$10^-3 m³ to 1 $$\times$$ 10^-2 m³ at 300 K against a constant pressure of 1$$\times$$10⁵ Nm^-2. The work done is :
Хариулт
(A)
-900 J
2
The enthalpies of combustion of carbon and carbon monoxide are -393.5 and -283 kJ mol-1 respectively. The enthalpy of formation of carbon monoxide per mole is :
Хариулт
(B)
-110.5 kJ
3
The conjugate base of H₂PO₄^- is :
Хариулт
(B)
$$HPO_4^{2-}$$
4
What is the equilibrium expression for the reaction
P₄ (s) + 5O₂ $$\leftrightharpoons$$ P₄O₁₀ (s)?
Хариулт
(B)
K_c = 1/[O₂]⁵
5
For the reaction, CO(g) + Cl₂(g) $$\leftrightharpoons$$ COCl₂(g) the $${{{K_p}} \over {{K_c}}}$$ is equal to :
Хариулт
(C)
1/RT
6
The equilibrium constant for the reaction N₂(g) + O₂(g) $$\leftrightharpoons$$ 2NO(g) at temperature T is 4 $$\times$$ 10^-4. The value of K_c for the reaction NO(g) $$\leftrightharpoons$$ $$1 \over 2$$N₂ (g) + $$1 \over 2$$O₂ (g) at the same temperature is :
Хариулт
(C)
50
7
The molar solubility (in ol L^-1) of a sparingly soluble salt MX₄ is "s". The corresponding solubility product is K_sp. 's' is given in term of K_sp by the relation :
Хариулт
(D)
s = (K_sp / 256)^1/5
8
Which one of the following has the minimum boiling point?
Хариулт
(B)
isobutane
9
Consider the acidity of the carboxylic acids:
(a) PhCOOH
(b) o – NO₂C₆H₄COOH
(c) p – NO₂C₆H₄COOH
(d) m – NO₂C₆H₄COOH
Which of the following order is correct?
Хариулт
(D)
(b) > (c) > (d) > (a)
10
Which of the following will have meso-isomer also?
Хариулт
(D)
2-3- dichlorobutane
11
Which one the following does not have sp² hybridized carbon?
Хариулт
(C)
Acetonitrile
12
Which of the following compound is not chiral?
Хариулт
(A)
1- chloropentane
13
Among the properties (a) reducing (b) oxidising (c) complexing, the set of properties shown by CN^– ion towards metal species is :
Хариулт
(A)
c, a
14
The compound formed on heating chlorobenzene with chloral in the presence concentrated sulphuric acid is
Хариулт
(D)
DDT
15
On mixing ethyl acetate with aqueous sodium chloride, the composition of the resultant solution is
Хариулт
(A)
CH₃COOC₂H₅ + NaCl
16
Which of the following undergoes reaction with 50% sodium hydroxide solution to give the corresponding alcohol and acid?
Хариулт
(D)
Benzaldehyde
17
Acetyl bromide reacts with excess of CH₃MgI followed by treatment with a saturated solution of NH₄Cl given
Хариулт
(C)
2- methyl -2- propanol
18
Which one of the following reduced with zinc and hydrochloric acid to give the corresponding hydrocarbon?
Хариулт
(B)
Butan -2-one
19
Which base is present in RNA but not in DNA?
Хариулт
(A)
Uracil
20
Insulin production and its action in human body are responsible for the level of diabetes. This compound belongs to which of the following categories?
Хариулт
(D)
A hormone
21
The compound formed in the positive test for nitrogen with the Lassaigne solution of an organic compound is
Хариулт
(A)
Fe₄[Fe(CN)₆]₃
22
The correct order of magnetic moments (spin only values in B.M.) among is :
(Atomic numbers: Mn = 25; Fe = 26, Co =27)
Хариулт
(A)
[MnCl₄]^2- > [CoCl₄]^-2 > [Fe(CN)₆]^-4
23
Which of the following is the strongest base ?
Хариулт
(D)
24
Amongst the following compounds, the optically active alkane having lowest molecular mass is
Хариулт
(A)
25
Rate of the reaction

is fastest when $$Z$$ is
Хариулт
(C)
$$Cl$$
26
The $$IUPAC$$ name of the compound is

Хариулт
(A)
$$3,3$$-dimethyl - $$1$$ - cyclohexanol
27
Among the following compounds which can be dehydrated very easily is
Хариулт
(A)
28
Of the following outer electronic configurations of atoms, the highest oxidation state is achieved by which one of them?
Хариулт
(D)
$$\left( {n - 1} \right){d^5}n{s^2}$$
29
The rate equation for the reaction 2A + B $$\to$$ C is found to be: rate k[A][B]. The correct statement in relation to this reaction is that the
Хариулт
(B)
values of k is independent of the initial concentration of A and B
30
Identify the correct statements regarding enzymes
Хариулт
(B)
Enzymes are specific biological catalysts that the posses well – defined active sites
31
Which of the following liquid pairs shows a positive deviation from Raoult’s law?
Хариулт
(D)
Benzene – methanol
32
Which one of the following statements is false?
Хариулт
(B)
Two sucrose solutions of same molality prepared in different solvents will have the same freezing point depression
33
Which one of the following aqueous solutions will exhibit highest boiling point?
Хариулт
(A)
0.01 M Na₂SO₄
34
For which of the following parameters the structural isomers C₂H₅OH and CH₃OCH₃ would be expected to have the same values? (Assume ideal behaviour)
Хариулт
(B)
Gaseous densities at the same temperature and pressure
35
In a hydrogen – oxygen fuel cell, combustion of hydrogen occurs to :
Хариулт
(D)
create potential difference between the two electrodes
36
Consider the following E^o values

$$E_{F{e^{3 + }}/F{e^{2 + }}}^o$$ = 0.77 V;

$$E_{S{n^{2 + }}/S{n}}^o$$ = -0.14 V

Under standard conditions the potential for the reaction

Sn(s) + 2Fe³⁺(aq) $$\to$$ 2Fe²⁺(aq) + Sn²⁺(aq) is :
Хариулт
(C)
0.91 V
37
The standard e.m.f of a cell, involving one electron change is found to be 0.591 V at 25^oC. The equilibrium constant of the reaction is (F = 96,500 C mol^-1: R = 8.314 JK^-1 mol^-1)
Хариулт
(C)
1.0 $$\times$$ 10¹⁰
38
The limiting molar conductivities Λ° for NaCl, KBr and KCl are 126, 152 and 150 S cm² mol^-1 respectively. The Λ° for NaBr is
Хариулт
(A)
128 S cm² mol^-1
39
In a cell that utilises the reaction Zn(s) + 2H⁺ (aq) $$\to$$ Zn2+(aq) + H2(g) addition of H₂SO₄ to cathode compartment, will
Хариулт
(C)
increase the E and shift equilibrium to the right
40
The $$E_{{M^{3 + }}/{M^{2 + }}}^o$$ values for Cr, Mn, Fe and Co are – 0.41, +1.57, + 0.77 and +1.97 V respectively. For which one of these metals the change in oxidation state form +2 to +3 is easiest?
Хариулт
(C)
Cr
41
In a first order reaction, the concentration of the reactant decreases from 0.8 M to 0.4 M in 15 minutes. The time taken for the concentration to change from 0.1 M to 0.025 M is
Хариулт
(A)
30 minutes
42
Consider the following nuclear reactions
$${}_{92}^{238}M \to {}_Y^XN + 2{}_2^4He$$
$${}_Y^XN \to {}_B^AL + 2{\beta ^ + }$$
The number of neutrons in the element L is
Хариулт
(B)
144
43
The half – life of a radioisotope is four hours. If the initial mass of the isotope was 200 g, the mass remaining after 24 hours undecayed is
Хариулт
(C)
3.125 g
44
Beryllium and aluminium exhibit many properties which are similar. But the two elements differ in :
Хариулт
(A)
exhibiting maximum covalency in compound
45
Which one the following statement regarding helium is incorrect?
Хариулт
(A)
It is used to fill gas balloons instead of hydrogen because it is lighter and non–inflammable
46
Excess of KI reacts with CuSO₄ solution and then Na₂S₂O₃ solution is added to it. Which of the statements is incorrect for this reaction?
Хариулт
(D)
CuI₂ is formed
47
Cerium (Z = 58) is an important member of the lanthanoids. Which of the following statements about cerium is incorrect?
Хариулт
(C)
The +4 oxidation state of cerium is not known in solutions
48
Which one of the following complexes in an outer orbital complex?
Хариулт
(B)
[Ni(NH₃)₆]²⁺
49
Which one the following has largest number of isomers? (R = alkyl group, en = ethylenediamine)
Хариулт
(B)
[Co(en)₂Cl₂]⁺
50
Coordination compound have great importance in biological systems. In this context which of the following statements is incorrect?
Хариулт
(A)
Chlorophylls are green pigments in plants and contains calcium
51
The coordination number of central metal atom in a complex is determined by :
Хариулт
(A)
the number of ligands around a metal ion bonded by sigma bonds
52
6.02 $$\times$$ 10²⁰ molecules of urea are present in 100 ml of its solution. The concentration of urea solution is
(Avogadro constant, N_A = 6.02 $$\times$$ 10²³ mol^-1)
Хариулт
(B)
0.01 M
53
To neutralise completely 20 mL of 0.1 M aqueous solution of phosphorous acid (H₃PO₃), the volume of 0.1 M aqueous KOH solution required is
Хариулт
(A)
40 mL
54
The ammonia evolved from the treatment of 0.30 g of an organic compound for the estimation of nitrogen was passed in 100 mL of 0.1 M sulphuric acid. The excess of acid required 20 mL of 0.5 M sodium hydroxide solution for complete neutralization. The organic compound is
Хариулт
(A)
urea
55
Which of the following sets of quantum numbers is correct for an electron in 4f orbital?
Хариулт
(A)
n = 4, l = 3, m = +1, s = + 1/2
56
Consider the ground state of Cr atom (Z = 24). The number of electrons with the azimuthal quantum numbers, l = 1 and 2 are respectively
Хариулт
(B)
12 and 5
57
The wavelength of the radiation emitted when in a hydrogen atom electron falls from infinity to stationary state 1, would be (Rydberg constant = 1.097 $$\times$$ 10⁷ m^-1)
Хариулт
(C)
91 nm
58
Which one of the following sets of ions represents the collection of isoelectronic species? (Atomic nos. : F = 9, Cl = 17, Na = 11, Mg = 12, Al = 13, K = 19, Ca = 20, Sc = 21)
Хариулт
(C)
K⁺, Ca²⁺, Sc³⁺, Cl^-
59
Which one of the following ions has the highest value of ionic radius?
Хариулт
(A)
O^2-
60
Among Al₂O₃, SiO₂, P₂O₃ and SO₂ the correct order of acid strength is
Хариулт
(B)
Al₂O₃ < SiO₂ < _P2O₃ < SO₂
61
The formation of the oxide ion O^2-(g) requires first an exothermic and then an endothermic step as shown below

O_(g) + e^- = $$O_{(g)}^{-}$$ $$\Delta $$H^o = -142 kJmol^-1

$$O_{(g)}^{-}$$ + e^- = $$O_{(g)}^{2-}$$ $$\Delta $$H^o = 844 kJmol^-1

This because
Хариулт
(A)
O^- ion will tend to resist the addition of another electron
62
The correct order of bond angles (smallest first) in H₂S, NH₃, BF₃ and SiH₄ is
Хариулт
(C)
H₂S < NH₃ < SiH₄ < BF₃
63
The bond order in NO is 2.5 while that in NO⁺ is 3. Which of the following statements is true for these two species?
Хариулт
(D)
Bond length in NO is greater than in NO⁺
64
The states of hybridization of boron and oxygen atoms in boric acid (H₃BO₃) are respectively
Хариулт
(D)
sp² and sp³
65
Which one of the following has the regular tetrahedral structure?
(Atomic nos : B = 5, S = 16, Ni = 28, Xe = 54)
Хариулт
(C)
$$BF_4^-$$
66
The maximum number of 90° angles between bond pair of electrons is observed in
Хариулт
(B)
sp³d² hybridization