Which one of the following statements is not true?
Answer
(B)
The pH of 1 $$\times$$ 10-8 M HCl is 8
2
The internal energy change when a system goes from state A to B is 40 kJ/mole. If the system goes from A to B by a reversible path and returns to state A by an irreversible path what would be the net change in internal energy?
Answer
(C)
Zero
3
In an irreversible process taking place at constant T and P and in which only pressure-volume work is being done, the change in Gibbs free energy (dG) and change in entropy (dS), satisfy the criteria :
Answer
(A)
(dS)V, E > 0, (dG)T, P < 0
4
The enthalpy change for a reaction does not depend upon :
Answer
(B)
the nature of intermediate reaction steps
5
The correct relationship between free energy change in a reaction and the corresponding equilibrium constant Kc is :
Answer
(C)
- $$\Delta G^o$$ = RT ln Kc
6
If at 298 K the bond energies of C - H, C - C, C = C and H - H bonds are respectively 414, 347, 615 and 435 kJ/mol, the value of enthalpy change for the reaction
H2C = CH2(g) + H2(g) $$\to$$ H3C - CH3(g) at 298 K will be :
Answer
(C)
- 125 kJ
7
The solubility in water of a sparingly soluble salt AB2 is 1.0 $$\times$$ 10-5 mol L-1. Its solubility product number will be :
Answer
(D)
4 $$\times$$ 10-15
8
Consider the reaction equilibrium
2 SO2 (g) + O2 (g) $$\leftrightharpoons$$ 2 SO3 (g); $$\Delta H^o$$ = -198 kJ
One the basis of Le Chatelier's principle, the condition favourable for the forward reaction is :
Answer
(B)
lowering the temperature and increasing the pressure
9
For the reaction equilibrium
N2O4 (g) $$\leftrightharpoons$$ 2NO2 (g)
the concentrations of N2O4 and NO2 at equilibrium are 4.8 $$\times$$ 10-2 and 1.2 $$\times$$ 10-2 mol L-1 respectively. The value of Kc for the reaction is
Answer
(B)
3 $$\times$$ 10-3 mol L-1
10
When rain is accompanied by a thunderstorm, the collected rain water will have a pH value :
Answer
(D)
slightly lower than that of rain water without thunderstorm
11
The IUPAC name of CH3COCH(CH3)2 is
Answer
(C)
3-methyl-2-butaone
12
In the anion HCOO$$-$$
the two carbon-oxygen bonds are found to be of equal length. What is the reason for it?
Answer
(B)
The anion HCOO-
has two resonating structures
13
The general formula CnH2nO2 could be for open chain
Answer
(A)
carboxylic acids
14
On mixing a certain alkane with chlorine and irradiating it with ultravioletlight, it forms only one
monochloroalkane. This alkane could be
Answer
(C)
neopentane
15
Butene-1 may be converted to butane by reaction with
Answer
(C)
Pd/H2
16
During dehydration of alcohols to alkenes by heating with conc. H2SO4 the initiation step is
Answer
(D)
protonation of alcohol molecule
17
When CH2 = CH - COOH is reduced with LiAlH4, the compound obtained will be
Answer
(A)
CH2 = CH - CH2OH
18
The correct order of increasing basic nature for the bases NH3, CH3NH2 and (CH3)2 NH is
Answer
(B)
NH3 < CH3NH2 < (CH3)2NH
19
Ethyl isocyanide on hydrolysis in acidic medium generates
Answer
(D)
ethylamine salt and methanoic acid
20
Complete hydrolysis of cellulose gives
Answer
(B)
D-glucose
21
Which one of the following statements is correct?
Answer
(A)
From a mixed precipitate of AgCl and AgI, ammonia solution dissolves only AgCl
22
Bottles containing C6H5l and C6H5CH2I lost their original labels. They were labelled A and B for testing A and B were separately taken in test tubes and boiled with NaOH solution. The end solution in each tube was made acidic with dilute HNO3 and then some AgNO3 solution was added. Substance B gave a yellow precipitate. Which one of the following statements is true for this experiment?
Answer
(D)
A was C6H5I
23
Among the following four structures $$i$$ to $$iv,$$
it is true that
Answer
(A)
only $$i$$ and $$ii$$ are chiral compounds
24
The reduction in atomic size with increase in atomic number is a characteristic of elements of
Answer
(D)
High atomic masses.
25
The atomic numbers of Vanadium (V), Chromium (cr), Manganese (Mn) and Iron (Fe), respectively, $$23,24,25$$ and $$26$$. Which one of these may be expected to have the higher second ionization enthalpy?
Answer
(A)
Cr
26
The reaction of chloroform with alcoholic $$KOH$$ and p-toluidine forms
Answer
(C)
27
The reason for double helical structure of $$DNA$$ is operation of
Answer
(B)
hydrogen bonding
28
A red solid is insolvable in water. However it becomes soluble if some $$K{\rm I}$$ is added to water. Heating the red solid in a test tube results in liberation of some violet colored fumes and droplets of a metal appear on the cooler parts of the test tube. The red solid is :
Answer
(A)
$$Hg{{\rm I}_2}$$
29
A pressure cooker reduces cooking time for food because
Answer
(A)
boiling point of water involved in cooking is increased
30
In a 0.2 molal aqueous solution of a weak acid HX the degree of ionization is 0.3. Taking kf for water as 1.85, the freezing point of the solution will be nearest to
Answer
(D)
-0.480oC
31
If liquids A and B form an ideal solution
Answer
(D)
the enthalpy of mixing is zero
32
Standard reduction electrode potentials of three metals A,B&C are respectively +0.5 V, -3.0 V & -1.2 V. The
reducing, powers of these metals are
Answer
(D)
B > C > A
33
For a cell reaction involving a two-electron change, the standard e.m.f. of the cell is found to be 0.295 V at 25oC. The equilibrium constant of the reaction at 25oC will be
Answer
(C)
1 $$\times$$ 1010
34
When during electrolysis of a solution of AgNO3, 9650 coulombs of charge pass through the electroplating
bath, the mass of silver deposited on the cathode will be :
Answer
(A)
10.8 g
35
For the redox reaction Zn(s) + Cu2+(0.1 M) $$\to$$ Zn2+(1M) + Cu(s) taking place in a cell, $$E_{cell}^o$$ is 1.10 volt. Ecell for the cell will be ($$2.303{{RT} \over F}$$ = 0.0591)
Answer
(B)
1.07 volt
36
Several blocks of magnesium are fixed to the bottom of a ship to :
Answer
(B)
prevent action of water and salt
37
The radionucleide $${}_{90}^{234}Th$$ undergoes two successive $$\beta$$ -decays followed by one $$\alpha$$-decay. The atomic number
and the mass number respectively of the resulting radionucleide are
Answer
(B)
90 and 230
38
The half-life of a radioactive isotope is three hours. If the initial mass of the isotope were 256 g, the mass of
it remaining undecayed after 18 hours would be
Answer
(D)
4.0 g
39
In respect of the equation k = Ae-Ea/RT in chemical kinetics, which one of the following statements is correct?
Answer
(B)
Ea is energy of activation
40
The rate law for a reaction between the substances A and B is given by Rate = k[A]n [B]m On doubling the concentration of A and halving the concentration of B, the ratio of the new rate to the earlier rate of the reaction will be as
Answer
(C)
2( n - m)
41
For the reaction system:
2NO(g) + O2(g) $$\to$$ 2NO2(g) volume is suddenly reduce to half its value by increasing the pressure on it. If the reaction is of first order with respect to O2 and second order with respect to NO, the rate of reaction will
Answer
(B)
increase to eight times of its initial value
42
Which one of the following substances has the highest proton affinity?
Answer
(B)
NH3
43
For making good quality mirrors, plates of float glass are used. These are obtained by floating molten glass
over a liquid metal which does not solidify before glass. The metal used can be :
Answer
(D)
mercury
44
Glass is a :
Answer
(A)
super-cooled liquid
45
What would happen when a solution of potassium chromate is treated with an excess of dilute nitric acid?
Answer
(A)
$$Cr_2O^{2-}_7$$ and H2O are formed
46
The atomic numbers of vanadium (V), Chromium (Cr), manganese (Mn) and iron (Fe) are respectively 23, 24, 25 and 26. Which one of these may be expected to have the highest second ionization enthalpy?
Answer
(A)
Cr
47
Which one of the following nitrates will leave behind a metal on strong heating?
Answer
(C)
Silver nitrate
48
Ammonia forms the complex ion [Cu(NH3)4]2+ with copper ions in alkaline solutions but not in acidic solutions. What is the reason for it?
Answer
(A)
In acidic solutions protons coordinate with ammonia molecules forming $$NH^+_4$$ ions and NH3
molecules are not available
49
The radius of La3+ (Atomic number of La = 57) is 1.06 Å. Which one of the following given values will be
closest to the radius of Lu3+ (Atomic number of Lu = 71) ?
Answer
(C)
0.85 Å
50
One mole of the complex compound Co(NH3)5Cl3, gives 3 moles of ions on dissolution in water. One mole of the same complex reacts with two moles of AgNO3 solution to yield two moles of AgCl (s). The structure of the complex is :
Answer
(D)
[Co(NH3)5Cl] Cl2
51
In the coordination compound, K4[Ni(CN)4], the oxidation state of nickel is :
Answer
(A)
0
52
The pair of species having identical shapes for molecules of both species is
Answer
(A)
XeF2, CO2
53
What volume of hydrogen gas at 273 K and 1 atm pressure will be consumed in obtaining 21.6 g of elemental boron (atomic mass = 10.8) from the reduction of boron trichloride by hydrogen?
Answer
(A)
67.2 L
54
25 ml of a solution of barium hydroxide on titration with a 0.1 molar solution of hydrochloric acid gave a litre value of 35 ml. The molarity of barium hydroxide solution was
Answer
(D)
0.07
55
The number of d-electrons retained in Fe2+ (At no of Fe = 26) ion is :
Answer
(C)
6
56
The orbital angular momentum for an electron revolving in an orbit is given by $$\sqrt {l(l + 1)} {h \over {2\pi }}$$. This momentum for an s-electron will be given by
Answer
(A)
zero
57
Which one of the following groupings represents a collection of isoelectronic species? (At. nos. : Cs : 55, Br : 35)
Answer
(A)
N3-, F-, Na+
58
In Bohr series of lines of hydrogen spectrum, the third line from the red end corresponds to which one of the following inter-orbit jumps of the electron for Bohr orbits in an atom of hydrogen
Answer
(A)
5 $$\to$$ 2
59
The de Broglie wavelength of a tennis ball of mass 60 g moving with a velocity of 10 meters per second is approximately
Answer
(D)
10-33 meters
60
According to the Periodic Law of elements, the variation in properties of elements is related to their
Answer
(B)
atomic numbers
61
Which one of the following is an amphoteric oxide?
Answer
(D)
ZnO
62
An ethar is more volatile than an alcohol having the same molecular formula. This is due to
Answer
(C)
inter-molecular hydrogen bonding in alcohols
63
Which one of the following pairs of molecules will have permanent dipole moments for both members
Answer
(B)
NO2 and O3
64
Which one of the following compounds has the smallest bond angle in its molecule?
