NSEC 2023 26th Nov Question Paper

NSEC 2023 26th Nov - Question 1

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The ligand with which the homoleptic octahedral complex of $$\text{Co}^{3+}$$ will be most stable is

A

Ethylenediamine tetra acetate ion

B

Dien (N-(2-aminoethyl)-1,2-ethanediamine)

C

Ethane-1,2-diamine

D

Ammonia

View Solution

NSEC 2023 26th Nov - Question 2

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Which of the following properties may have positive values of $$\Delta H$$?

(i) Lattice enthalpy     (ii) Hydration enthalpy

(iii) Electron gain enthalpy for noble gases     (iv) Ionisation enthalpy

A

(i) and (ii)

B

(iii) and (iv)

C

Only (iv)

D

(ii), (iii) and (iv)

View Solution

NSEC 2023 26th Nov - Question 3

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The correct IUPAC name of potassium permanganate is

A

potassium tetraoxomanganate(VI)

B

potassium tetraoxidopermanganate(VII)

C

potassium tetraoxidomanganese(VII)

D

potassium tetraoxidomanganate(VII)

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NSEC 2023 26th Nov - Question 4

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Which of the following statements is true with respect to sodium salts of oxoanions of phosphorus $$\text{NaH}_2\text{PO}_2$$ and $$\text{Na}_2\text{HPO}_3$$?

A

$$\text{NaH}_2\text{PO}_2$$ is reducing and $$\text{Na}_2\text{HPO}_3$$ is oxidizing

B

$$\text{NaH}_2\text{PO}_2$$ is more reducing than $$\text{Na}_2\text{HPO}_3$$

C

$$\text{NaH}_2\text{PO}_2$$ is more oxidizing than $$\text{Na}_2\text{HPO}_3$$

D

$$\text{NaH}_2\text{PO}_2$$ is oxidizing and $$\text{Na}_2\text{HPO}_3$$ is reducing

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NSEC 2023 26th Nov - Question 5

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The fluorides of xenon, $$\text{XeF}_n$$ with n equal to 2 or 4 or 6, which on complete hydrolysis give back xenon as one of the products, are

I. $$\text{XeF}_2$$

II. $$\text{XeF}_4$$

III. $$\text{XeF}_6$$

A

II only

B

I and II

C

III only

D

I, II and III

View Solution

NSEC 2023 26th Nov - Question 6

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If an element after oganesson, Og, of atomic number 118 and electronic configuration [Rn] $$5f^{14} 6d^{10} 7s^2 7p^6$$, was discovered, in which of the following orbitals will the 119th electron be accommodated?

A

7d

B

6f

C

8s

D

5g

View Solution

NSEC 2023 26th Nov - Question 7

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The number of two-center-two-electron and three-center-two-electron bonds in $$[\text{Al(BH}_4)_3]$$ are respectively

A

twelve and zero

B

twelve and three

C

six and six

D

nine and three

View Solution

NSEC 2023 26th Nov - Question 8

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Identify the correct matching of the following oxides in column M with their property in column N.

A

(i)-(p), (ii)-(q), (iii)-(r)

B

(i)-(q), (ii)-(r), (iii)-(p)

C

(i)-(r), (ii)-(q), (iii)-(p)

D

(i)-(r), (ii)-(p), (iii)-(q)

View Solution

NSEC 2023 26th Nov - Question 9

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In each of the following reactions the role of water is 

(i) $$\text{H}_2\text{O} + \text{HCl} \rightarrow \text{H}_3\text{O}^+ + \text{Cl}^-$$ 

(ii) $$6\text{H}_2\text{O} + \text{Mg}^{2+} \rightarrow [\text{Mg(H}_2\text{O})_6]^{2+}$$ 

(iii) $$2\text{H}_2\text{O} + 2\text{F}_2 \rightarrow 4\text{HF} + \text{O}_2$$

A

(i) oxidant, (ii) reductant, (iii) base

B

(i) reductant, (ii) oxidant, (iii) base

C

(i) base, (ii) base, (iii) reductant

D

(i) acid, (ii) base, (iii) reductant

View Solution

NSEC 2023 26th Nov - Question 10

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The correct order of the following oxidizing agents in basic aqueous medium, given that 

$$\text{CrO}_4^{2-}/\text{Cr}^{3+}$$ has $$E^\circ = -0.11$$ V, 

$$\text{FeO}_4^{2-}/\text{Fe}^{3+}$$ has $$E^\circ = +0.72$$ V and 

$$\text{MnO}_4^{2-}/\text{Mn}^{3+}$$ has $$E^\circ = +0.46$$ V, is

A

$$[\text{CrO}_4]^{2-} > [\text{FeO}_4]^{2-} > [\text{MnO}_4]^{2-}$$

B

$$[\text{FeO}_4]^{2-} > [\text{MnO}_4]^{2-} > [\text{CrO}_4]^{2-}$$

C

$$[\text{CrO}_4]^{2-} > [\text{MnO}_4]^{2-} > [\text{FeO}_4]^{2-}$$

D

$$[\text{MnO}_4]^{2-} > [\text{FeO}_4]^{2-} > [\text{CrO}_4]^{2-}$$

View Solution

NSEC 2023 26th Nov - Question 11

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The correct order of ionic radii of $$\text{Rb}^+$$, $$\text{Br}^-$$, $$\text{Sr}^{2+}$$ and $$\text{Se}^{2-}$$ is

A

$$\text{Rb}^+ < \text{Br}^- < \text{Sr}^{2+} < \text{Se}^{2-}$$

B

$$\text{Sr}^{2+} < \text{Rb}^+ < \text{Br}^- < \text{Se}^{2-}$$

C

$$\text{Se}^{2-} < \text{Br}^- < \text{Sr}^{2+} < \text{Rb}^+$$

D

$$\text{Se}^{2-} < \text{Sr}^{2+} < \text{Rb}^+ < \text{Br}^-$$

View Solution

NSEC 2023 26th Nov - Question 12

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Consider the following statements. 

(i) Calcination is carried out in absence of air below the melting point of the ore

(ii) Roasting and calcination are carried out in presence of flux

(iii) Calcination is carried out in limited supply of air above the melting point of the ore 

(iv) Roasting is carried out in air below the melting point of ore. The correct set of statements is

A

(i) and (iv)

B

(ii) and (iii)

C

(i), (iii) and (iv)

D

(iii) and (iv)

View Solution

NSEC 2023 26th Nov - Question 13

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The cobalt complexes (I) and (II) given below are examples of

A

linkage isomers

B

coordination isomers

C

ligand isomers

D

coordination position isomers

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NSEC 2023 26th Nov - Question 14

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The magnetic moment, in units of BM, of copper in $$[\text{Cu(H}_2\text{O})_4]^{2+}$$ and $$[\text{Cu(NH}_3)_4]^{2+}$$ respectively is

A

1.73 and 0

B

1.73 and 1.73

C

2.83 and 2.83

D

0 and 2.83

View Solution

NSEC 2023 26th Nov - Question 15

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In qualitative inorganic analysis of a water-soluble salt mixture, salt AB together with salt XY, both the cations were identified as sulphides. In the tests for anions the sodium carbonate extract when treated with $$\text{AgNO}_3$$ gave a yellowish precipitate soluble with difficulty in $$\text{NH}_4\text{OH}$$ while the other anion can be confirmed with the brown ring test. Given that $$K_{sp}$$ for AS is $$1 \times 10^{-44}$$ and for XS is $$1.4 \times 10^{-24}$$, identify the INCORRECT statement about the analysis.

A

$$\text{H}_2\text{S}$$ can be used under appropriate conditions of pH to separate and identify the cations

B

Cation A will be precipitated under acidic condition as the concentration of sulphide ions required is low

C

The anions are $$\text{NO}_3^-$$ and $$\text{Cl}^-$$

D

Cation X will be precipitated as sulphide under alkaline condition, as the concentration of sulphide ions required is very high

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NSEC 2023 26th Nov - Question 16

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The correct statement about the solubilities of Group 2 hydroxides is

A

The solubilities increase because lattice energy increases as we go down Group 2

B

The solubilities increase because lattice energy decreases as we go down Group 2

C

The solubilities decrease because atomic size increases as we go down Group 2

D

The solubilities decrease because lattice energy decreases as we go down Group 2

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NSEC 2023 26th Nov - Question 17

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A solution of $$\text{CuSO}_4 \cdot 5\text{H}_2\text{O}$$ in methanol has $$[\text{Cu}^{2+}] = 1.00$$ mg per 1000 g of methanol. The molarity of $$\text{Cu}^{2+}$$ in this solution is $$Y \times 10^{-5}$$ mol $$\text{L}^{-1}$$. Given that the density of methanol is 0.792 g $$\text{mL}^{-1}$$, Y is

A

1.57

B

5.04

C

1.25

D

3.99

View Solution

NSEC 2023 26th Nov - Question 18

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Following is the reaction flow chart for manganese oxidocomplexes under different alkaline pH conditions. Compounds (S) and (T) respectively are

A

$$\text{S} = \text{MnO(OH)}_2$$ and $$\text{T} = \text{Mn(OH)}_2$$

B

$$\text{S} = \text{MnO}_2$$ and $$\text{T} = \text{MnO(OH)}$$

C

$$\text{S} = \text{MnO}_4^{2-}$$ and $$\text{T} = \text{MnO(OH)}$$

D

$$\text{S} = \text{MnO}_4^{2-}$$ and $$\text{T} = \text{MnO}_2$$

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NSEC 2023 26th Nov - Question 19

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The correct order of relative strength for the following nucleophilic species, namely 

I) $$\text{NH}_2^-$$ 

II) $$\text{OCH}_3^-$$  

III) $$\text{CH}_3\text{COO}^-$$  

IV) $$\text{CH}_3\text{OH}$$ 

A

IV > III > II > I

B

II > III > IV > I

C

I > II > IV > III

D

I > II > III > IV

View Solution

NSEC 2023 26th Nov - Question 20

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The product obtained on reaction of optically pure 1-bromo-1-phenyl ethane with $$\text{CH}_3\text{OH}$$ is

A

phenyl ethene

B

1-methoxy-1-phenyl ethane with inverted configuration only

C

1-methoxy-1-phenyl ethane with retention of configuration

D

a racemic mixture of 1-methoxy-1-phenyl ethane

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NSEC 2023 26th Nov - Question 21

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An alkane [X] contains five $$1º$$, two $$2º$$, one $$3º$$ and one $$4º$$ carbon atoms. The IUPAC name of [X] is

A

2,4,4-trimethylhexane

B

3,5-dimethylheptane

C

2,4-dimethylheptane

D

4,4-dimethylheptane

View Solution

NSEC 2023 26th Nov - Question 22

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The number of isomeric alkenes with molecular formula $$\text{C}_5\text{H}_{10}$$, taking stereoisomers into account, is

A

4

B

5

C

6

D

7

View Solution

NSEC 2023 26th Nov - Question 23

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At $$0^\circ\text{C}$$, 1 equivalent of bromine is added to 2,4-hexadiene to produce 4,5-dibromo-2-hexene and its isomer X. X is

A

5,5-dibromo-2-hexene

B

2,5-dibromo-3-hexene

C

2,2-dibromo-3-hexene

D

2,3-dibromo-4-hexene

View Solution

NSEC 2023 26th Nov - Question 24

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Which of the following is or are examples of an acetal?

A

I and II

B

III and IV

C

Only IV

D

I, II and III

View Solution

NSEC 2023 26th Nov - Question 25

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The compound which can be produced by double aldol condensation of 1-phenyl-1,2-propanedione is

A

P

B

Q

C

R

D

S

View Solution

NSEC 2023 26th Nov - Question 26

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2,2-Dimethyl-1,3-propanediol is formed by heating 2-methylpropanal with an excess of formaldehyde and $$\text{Ca(OH)}_2$$. The sequence of reactions taking place in this synthesis is

A

dehydrogenation to 2-methyl-2-propenal followed by addition of formaldehyde

B

dehydrogenation to penta-2,3-diene followed by addition of formaldehyde

C

a crossed aldol reaction followed by a crossed Cannizzaro reaction

D

a crossed Cannizzaro reaction followed by a crossed aldol reaction

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NSEC 2023 26th Nov - Question 27

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The number of different types of dipeptides produced using a mixture of glycine and L-valine, and the number of optically active dipeptides formed in this mixture, will be

A

Four dipeptides, all optically active

B

Two dipeptides, all optically active

C

Four dipeptides, three optically active

D

Two dipeptides, none optically active

View Solution

NSEC 2023 26th Nov - Question 28

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Predict the major product in the following reaction, where PCC is pyridinium chlorochromate.

A

B

C

D

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NSEC 2023 26th Nov - Question 29

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Find out the product in the following reaction.

A

B

C

D

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NSEC 2023 26th Nov - Question 30

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The products obtained on reaction of biphenyl (Ph-Ph) with nitrating mixture, $$\text{HNO}_3$$ and $$\text{H}_2\text{SO}_4$$, are

A

B

C

D

View Solution

NSEC 2023 26th Nov - Question 31

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Chlorination of propane gives four dichloro products. One of them is optically active. The number of trichloro products possible from the optically active dichloro product, excluding stereoisomers, is

A

1

B

2

C

3

D

4

View Solution

NSEC 2023 26th Nov - Question 32

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The suitable reagent for the following transformation is

A

Na / liq. $$\text{NH}_3$$

B

$$\text{H}_2$$ and Pd/C

C

$$\text{LiAlH}_4$$

D

Zn-Hg, HCl and heat

View Solution

NSEC 2023 26th Nov - Question 33

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Column A represents a set of functional groups and Column B their respective electronic effects The correct match is:

[EDG: Electron donating group and EWG: Electron withdrawing group]

A

a

B

b

C

c

D

d

View Solution

NSEC 2023 26th Nov - Question 34

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The correct order of reactivity of $$-\text{CHO}$$, $$-\text{COR}$$, $$-\text{COOR}$$ and $$-\text{CONR}_2$$ groups toward MeMgI in ether is

A

$$-\text{CONR}_2 > -\text{COOR} > -\text{COR} > -\text{CHO}$$

B

$$-\text{CHO} > -\text{COR} > -\text{COOR} > -\text{CONR}_2$$

C

$$-\text{CONR}_2 > -\text{CHO} > -\text{COR} > -\text{COOR}$$

D

$$-\text{CHO} > -\text{CONR}_2 > -\text{COOR} > -\text{COR}$$

View Solution

NSEC 2023 26th Nov - Question 35

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The plots of energy density, that is energy per unit area, against wavelength for blackbody radiation at various temperatures are given below. The correct option among the following is:

(i) $$T_1 > T_2 > T_3 > T_4 > T_5$$  

(ii) As temperature increases, the wavelength at which the intensity is maximum shifts towards the higher energy regions of the electromagnetic spectrum 

(iii) Radiations of all wavelengths are emitted, absorbed, reflected, and refracted by the black body 

(iv) The total energy density increases as the temperature is decreased. 

The correct option among the following is

A

(i) and (ii)

B

(ii) and (iii)

C

(i), (iii) and (iv)

D

(ii), (iii) and (iv)

View Solution

NSEC 2023 26th Nov - Question 36

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A student adds 'x' g of iron (Fe) powder to dil. HCl and measures the work done by the reaction between HCl and the added Fe to be 1000 J. If the experiment was conducted at a constant pressure of 1 atm at $$27^\circ\text{C}$$, the mass of Fe powder added is

A

22.4 g

B

2.24 g

C

11.2 g

D

1.12 g

View Solution

NSEC 2023 26th Nov - Question 37

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Antacids are medicines that temporarily neutralize the acid in the stomach and prevent heartburns. The volume of an antacid syrup containing 2.9 g of $$\text{Mg(OH)}_2$$ per 100 mL to be given to a patient whose stomach contains 2 L of gastric juice with HCl concentration of $$6.0 \times 10^{-3}$$ M is, given that the molar mass of $$\text{Mg(OH)}_2$$ is 58.0 g $$\text{mol}^{-1}$$,

A

4.0 mL

B

7.8 mL

C

12.0 mL

D

120 mL

View Solution

NSEC 2023 26th Nov - Question 38

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A half-cell reaction represented by (i) below, namely 

$$\text{Fe(OH)}_2(s) + 2e^- \rightarrow \text{Fe}(s) + 2\text{OH}^-(aq)$$ with $$E^\circ = -0.9$$ V, takes place in two different electrochemical cells, I and II, in which the other half cell reactions are 

(ii) $$\text{Al}^{3+}(aq) + 3e^- \rightarrow \text{Al}(s)$$ with $$E^\circ = -1.7$$ V and 

(iii) $$\text{AgBr}(s) + e^- \rightarrow \text{Ag}(s) + \text{Br}^-(aq)$$ with $$E^\circ = -0.07$$ V respectively. 

The correct option that represents the redox reactions in cells I and II is

A

Fe is oxidised in cell I and Fe is oxidised in cell II

B

Fe is oxidised in cell I and Fe is reduced in cell II

C

Fe is reduced in cell I and Fe is reduced in cell II

D

Fe is reduced in cell I and Fe is oxidised in cell II

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NSEC 2023 26th Nov - Question 39

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The following are the concentration versus time plots of the reactants and products represented by the reaction 

$$\text{L}(g) + 2\text{M}(g) \rightarrow \text{N}(g) + 3\text{O}(g)$$. 

The curves that represent M(g) and N(g) qualitatively are respectively

A

X, Y

B

Y, U

C

V, Y

D

U, X

View Solution

NSEC 2023 26th Nov - Question 40

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The current produced due to photoelectric effect

A

increases with the increase of frequency of the incident radiation

B

increases with the increase in intensity of the incident radiation

C

decreases with time of irradiation

D

is independent of the intensity of incident radiation

View Solution

NSEC 2023 26th Nov - Question 41

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The property of radiation that is not different at various regions of the electromagnetic spectrum is

A

energy

B

frequency

C

velocity

D

wavelength

View Solution

NSEC 2023 26th Nov - Question 42

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Among the following, the correct statements about the compressibility factor (Z) of real gases are 

(i) If $$Z < 1$$, intermolecular repulsive forces are more dominant

(ii) If $$Z < 1$$, intermolecular attractive forces are more dominant

(iii) If $$Z > 1$$, intermolecular repulsive forces are more dominant

(iv) If $$Z > 1$$, intermolecular attractive forces are more dominant

A

(i) and (iv)

B

(i) and (iii)

C

(ii) and (iv)

D

(ii) and (iii)

View Solution

NSEC 2023 26th Nov - Question 43

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The figure represents the processes AB, BC and CA undertaken by a certain mass of an ideal gas. Along the path AB, the gas is isothermally compressed with release of 800 J heat to the surroundings. It is then compressed adiabatically along the path BC and the work done is 500 J. The gas then returns to the state A along path CA and absorbs 100 J heat from the surroundings. The work done by the gas along the path CA is

A

$$-300$$ J

B

$$-900$$ J

C

$$-600$$ J

D

$$-400$$ J

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NSEC 2023 26th Nov - Question 44

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Two flasks I and II of equal volume are evacuated and connected by a tube of negligible volume fitted with a stopcock. They are then placed in two different constant temperature baths of 250 K and 750 K respectively. 20 moles of an ideal gas are introduced into the system of these flasks through the stopcock. When the system reaches equilibrium, the ratio of the moles of the gas in flasks I and II is

A

$$1 \colon 1$$

B

$$2 \colon 1$$

C

$$3 \colon 1$$

D

$$4 \colon 1$$

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NSEC 2023 26th Nov - Question 45

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When a certain amount of a univalent salt AB of molar mass 54 g $$\text{mol}^{-1}$$ was dissolved in 0.1 $$\text{dm}^3$$ of water, the relative lowering of the vapour pressure was found to be 3.55%. Assuming complete dissociation of the salt under the given condition and taking the density of water as 1 g $$\text{cm}^{-3}$$, the molality of the resulting solution is

A

0.5 m

B

1.0 m

C

2.0 m

D

4.0 m

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NSEC 2023 26th Nov - Question 46

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The rate constant values for the decay of radioisotopes X and Y, used in radio-medicine, are 0.05 $$\text{h}^{-1}$$ and 0.025 $$\text{h}^{-1}$$ respectively. In a hospital, at a time $$t_0$$ the activity of a sample of X was found to be twice that of Y. The activities of the two radioisotopes will be approximately equal when the time elapsed is

A

twice the half-life of Y

B

twice the half-life of X

C

equal to the half-life of X

D

equal to half the half-life of Y

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NSEC 2023 26th Nov - Question 47

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Latimer diagrams are the compact representations of electrochemical equilibria in substances of multiple oxidation states. The value of the potential x in the Latimer diagram of gold at pH equal to 1.0 is

A

2.72 V

B

3.18 V

C

$$-3.18$$ V

D

1.36 V

View Solution

NSEC 2023 26th Nov - Question 48

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Electrolysis of aqueous $$\text{CuSO}_4$$ (0.1 M) was carried out in two cells I and II. In I, the electrodes are of Cu and in II they were of Pt. As the electrolysis proceeds the pH of the electrolyte solution will

A

decrease in II and remain the same in I

B

remain the same in both I and II

C

increase in both I and II

D

increase in I and decrease in II

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NSEC 2023 26th Nov - Question 49

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Choose the correct statements regarding zeolites.

A

Silicon atoms are replaced by aluminium atoms in the zeolites

B

The pores and cavities of the zeolites as well as size and shape of reactant decides the reactions taking place in the zeolites

C

The cracking of hydrocarbons and isomerisation reactions are catalyzed by zeolites in the petrochemical industries

D

Zeolites act as molecular sieves and can separate the molecules of different sizes

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NSEC 2023 26th Nov - Question 50

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Crystalline iron(III) nitrate nonahydrate, $$\text{Fe(NO}_3)_3 \cdot 9\text{H}_2\text{O}$$, has a very pale violet colour. When added to water, the crystals dissolve to form a brown solution. Treatment of this brown solution with concentrated nitric acid yields a very pale violet solution while treatment with HCl yields a yellow solution. Identify the correct statements regarding the above observations.

A

The brown colour is due to $$[\text{Fe(OH)(H}_2\text{O})_5]^{2+}$$ and $$[\text{Fe(OH)}_2(\text{H}_2\text{O})_4]^+$$

B

Violet colour is due to $$[\text{Fe(H}_2\text{O})_6]^{3+}$$ and yellow colour due to $$[\text{FeCl}_4]^-$$

C

Addition of $$\text{HNO}_3$$ shifts the equilibrium $$[\text{Fe(H}_2\text{O})_6]^{3+} + \text{H}_2\text{O} \rightleftharpoons [\text{Fe(OH)(H}_2\text{O})_5]^{2+} + \text{H}_3\text{O}^+$$ to left giving pale violet colour

D

Addition of $$\text{HNO}_3$$ shifts the equilibrium $$[\text{Fe(H}_2\text{O})_6]^{3+} + \text{H}_2\text{O} \rightleftharpoons [\text{Fe(OH)(H}_2\text{O})_5]^{2+} + \text{H}_3\text{O}^+$$ to right giving violet colour

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NSEC 2023 26th Nov - Question 51

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The optically active compounds from the following are

A

B

C

D

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NSEC 2023 26th Nov - Question 52

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3-chlorotoluene is reacted with a mixture of conc. $$\text{H}_2\text{SO}_4$$ and $$\text{HNO}_3$$. The products formed are

A

B

C

D

View Solution

NSEC 2023 26th Nov - Question 53

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2,4,6-trinitrophenol is more acidic than phenol. Identify the correct statements.

A

$$pK_a$$ for 2,4,6-trinitrophenol is less than that of phenol

B

phenol is stabilized by intramolecular $$\pi$$ hydrogen bonding

C

The conjugate base of 2,4,6-trinitrophenol delocalizes the negative charge on the oxygen atom to a very large extent

D

The conjugate base of phenol delocalizes the negative charge to a greater extent than the conjugate base of 2,4,6-trinitrophenol

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NSEC 2023 26th Nov - Question 54

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The correct statements for 1,3-butadiene from the following are

A

Molar addition of $$\text{Br}_2$$ yields only 1,4-dibromo-2-butene as the major product when the reaction is performed for longer time period

B

Molar addition of $$\text{Br}_2$$ yields only 1,2-dibromo-2-butene for longer time period

C

$$\text{C}_1 - \text{C}_2$$ and $$\text{C}_3 - \text{C}_4$$ bonds are slightly longer than a $$\text{C} = \text{C}$$ bond

D

$$\text{C}_2 - \text{C}_3$$ single bond is slightly shorter than a $$\text{C} - \text{C}$$ bond

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NSEC 2023 26th Nov - Question 55

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Which of the following representations will exhibit cis-trans isomerism?

A

B

C

D

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NSEC 2023 26th Nov - Question 56

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For an elementary dimerization reaction of the type $$2\text{R} \rightarrow \text{R}_2$$, the value of the steric factor was found to be 2.5. This indicates that

A

the experimentally obtained rate is 2.5 times faster than the theoretical rate

B

ratio of the number of collisions calculated from collision theory and that actually take place is $$1 \colon 2.5$$

C

the activation energy of the reaction is the same for both the experimental and calculated values

D

the molecules of reactant R may be of some complex structure

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NSEC 2023 26th Nov - Question 57

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The correct statements among the following are

A

The charge on the diffused layer of AgI colloidal solution by the addition of few drops of dilute aqueous solution of KI to an aqueous solution of $$\text{AgNO}_3$$ is negative

B

The charge on the diffused layer of AgI colloidal solution by the addition of few drops of dilute aqueous solution of $$\text{AgNO}_3$$ to an aqueous solution of KI is positive

C

When the ionic strength of a colloidal solution is increased, thickness of the double layer is increased, and the colloid gets precipitated

D

When the ionic strength of a colloidal solution is increased, thickness of the double layer is decreased, and the colloid gets precipitated

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NSEC 2023 26th Nov - Question 58

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In reverse osmosis the flow of solvent across a semi permeable membrane occurs

A

when hydrostatic pressure is greater than osmotic pressure

B

when hydrostatic pressure is lower than osmotic pressure

C

from higher concentrated solution to lower concentrated solution

D

from lower concentrated solution to higher concentrated solution

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NSEC 2023 26th Nov - Question 59

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Given below is the plot of pH versus volume of NaOH added in an acid-base titration. The correct statements among the following are

A

Before the equivalence point, a series of buffer solutions determine the pH

B

The graph represents the titration of a strong acid with NaOH

C

At the equivalence point, hydrolysis of the anion of the acid determines the pH

D

After the equivalence point acid and salt buffer solution determines the pH

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NSEC 2023 26th Nov - Question 60

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The correct statements among the following are

A

The probability density $$\psi^2$$ for a hydrogen atom is zero at $$r = 0$$

B

In an atom, orbitals with the same quantum number have different energies

C

The energy of a given orbital with same principal quantum number decreases as the atomic number Z increases

D

For a given atomic number, the configuration having the maximum number of parallel spins is of the lowest energy than any other arrangement arising from the same configuration

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