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Q 1. The enolic form of a acetone contains

9 sigma bonds, 1 pi bond and 2 lone pairs

B

8 sigma bonds, 2 pi bonds and 2 lone pairs

C

10 sigma bonds, 1 pi bond and 1 lone pair

D

9 sigma bonds, 2 pi bonds and 1 lone pair

Explanation

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Q 2. Following reaction occurs in an automobile
{tex} 2 \mathrm { C } _ { 8 } \mathrm { H } _ { 18 } ( \mathrm { g } ) + 25 \mathrm { O } _ { 2 } ( \mathrm { g } ) \longrightarrow 16 \mathrm { CO } _ { 2 } ( \mathrm { g } ) + 18 \mathrm { H } _ { 2 } \mathrm { O } ( \mathrm { g } ) {/tex}
The sign of {tex}\Delta\mathrm H, \Delta\mathrm S {/tex} and {tex}\Delta\mathrm G {/tex} would be

A

{tex} + , - , + {/tex}

{tex} - , + , - {/tex}

C

{tex} - , + , + {/tex}

D

{tex} + , + , - {/tex}

Explanation

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Q 3. What is {tex} \mathrm { Z } {/tex} in the following sequence of reactions?
{tex} \mathrm { Z } \xrightarrow { \mathrm { PCl } _ { 5 } } \mathrm { X }\xrightarrow { \text { Alc. } \mathrm { KOH } } \mathrm { Y } \xrightarrow [ ( \mathrm { ii } ) \mathrm { H } _ { 2 } \mathrm { O } ; \text { boil } ]{ ( \mathrm { i } )\ \mathrm { Conc. } \mathrm { H } _ { 2 } \mathrm { SO } _ { 4 } } \mathrm { Z } {/tex}

A

{tex} \mathrm { CH } _ { 3 } \mathrm { CH } _ { 2 } \mathrm { CH } _ { 2 } \mathrm { OH } {/tex}

{tex} \mathrm { CH } _ { 3 } \mathrm { CH } ( \mathrm { OH } ) \mathrm { CH } _ { 3 } {/tex}

C

{tex} \left( \mathrm { CH } _ { 3 } \mathrm { CH } _ { 2 } \right) _ { 2 } \mathrm { CHOH } {/tex}

D

{tex} \mathrm { CH } _ { 3 } \mathrm { cH } = \mathrm { CH } _ { 2 } {/tex}

Explanation

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Q 4. Complexes formed in the following methods are
I. Mond's process for purification of nickel.
II. Removal of lead poisoning from the body.
III. Cyanide process for extraction of silver.
IV. Froth flotation process for separation of {tex}\mathrm {ZnS}{/tex} from galena ore by using depressant.

A

{tex} \mathrm { I }- \mathrm { Ni } ( \mathrm { CO } ) _ { 4 },\ {\mathrm {II}- \left[ \mathrm { Pb } ( \mathrm { ED } \mathrm { TA } ] ^ { 2 - } \right.},\ {\mathrm {III-} \left[ \mathrm { Ag } ( \mathrm { CN } ) _ { 2 } \right] ^ { - },\ \mathrm {IV-} \left[ \mathrm { Zn } ( \mathrm { CN } ) _ { 2 } \right] } {/tex}

{tex} \mathrm { I }- \mathrm { Ni } ( \mathrm { CO } ) _ { 4 },\ {\mathrm {II}- \left[ \mathrm { Pb } ( \mathrm { ED } \mathrm { TA } ] ^ { 2 - } \right.},\ {\mathrm {III-} \left[ \mathrm { Ag } ( \mathrm { CN } ) _ { 2 } \right] ^ { - },\ \mathrm {IV-} \left[ \mathrm { Zn } ( \mathrm { CN } ) _ { 4 } \right]^{2-} } {/tex}

C

{tex} \mathrm { I }- \mathrm { Ni } ( \mathrm { CO } ) _ { 6 },\ {\mathrm {II}- \left[ \mathrm { Pb } ( \mathrm { ED } \mathrm { TA } ] ^ { 4 - } \right.},\ {\mathrm {III-} \left[ \mathrm { Ag } ( \mathrm { CN } ) _ { 2 } \right] ^ { - },\ \mathrm {IV-} \left[ \mathrm { Zn } ( \mathrm { CN } ) _ { 6 } \right]^{4-} } {/tex}

D

{tex} \mathrm { I }- \mathrm { Ni } ( \mathrm { CO } ) _ { 4 },\ {\mathrm {II}- \left[ \mathrm { Pb } ( \mathrm { ED } \mathrm { TA } ] ^ { 2 - } \right.},\ {\mathrm {III-} \left[ \mathrm { Ag } ( \mathrm { CN } ) _ { 4 } \right] ^ { 3- },\ \mathrm {IV-} \left[ \mathrm { Zn } ( \mathrm { CN } ) _ { 4 } \right]^{2-} } {/tex}

Explanation



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Q 5. An example of electrophilic substitution reaction is:

A

Chlorination of methane

B

Conversion of methyl chloride to methyl alcohol

Nitration of benzene

D

Formation of ethylene from ethyl alcohol.

Explanation

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Q 6. Structurally biodegradable detergents, should contain

A

normal alkyl chain

branched alkyl chain

C

phenyl side chain

D

cyclohexyl side chain

Explanation

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Q 7. Ozone hole refers to:

A

Increase in concentration of ozone

B

Hole in ozone layer

C

Reduction in thickness of ozone layer in troposphere

Reduction in thickness of ozone layer in stratsophere

Explanation

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Q 8. Which of the following does not represent the correct order of the properties indicated?

{tex} \mathrm { Ni } ^ { 2 + } > \mathrm { Cr } ^ { 2 + } > \mathrm { Fe } ^ { 2 + } > \mathrm { Mn } ^ { 2 + } {/tex}(size)

B

{tex} \mathrm { Sc } > \mathrm { Ti } > \mathrm { Cr } > \mathrm { Mn } {/tex} (size)

C

{tex} \mathrm { Mn } ^ { 2 + } > \mathrm { Ni } ^ { 2 + } < \mathrm { Co } ^ { 2 + } < \mathrm { Fe } ^ { 2 + } {/tex} (unpaired electron)

D

{tex} \mathrm { Fe } ^ { 2 + } > \mathrm { Co } ^ { 2 + } > \mathrm { Ni } ^ { 2 + } > \mathrm { Cu } ^ { 2 + } {/tex} (unpaired electron)

Explanation

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Q 9. Match the columns

Column-IColumn-II
(A) {tex} \mathrm { C } _ { 2 } \mathrm { H } _ { 6 } \xrightarrow { \mathrm { Cl } _ { 2 } / \mathrm { UV\ light }} { \mathrm { C } _ { 2 } \mathrm { H } _ { 5 } \mathrm { Cl } }{/tex}(p) Finkelstein reaction
(B) {tex} \mathrm { C } _ { 6 } \mathrm { H } _ { 5 } \mathrm { NH } _ { 2 } \xrightarrow [ 273 - 278 \mathrm { K }] { \mathrm { NaNO } _ { 2 } + \mathrm { HCl } / \mathrm { Cu } _ { 2 } \mathrm { Cl } _ { 2 } }{ \mathrm { C } _ { 6 } \mathrm { H } _ { 5 } \mathrm { Cl } }{/tex}(q) Free radical substitution
(C) {tex} \mathrm { CH_3Cl }+ \mathrm {NaI }\rightarrow \mathrm { CH_3I } + \mathrm { NaCl } {/tex}(r) Swarts reaction
(D) {tex} \mathrm { CH_3-Br }+ \mathrm {AgF }\rightarrow \mathrm { CH_3F } + \mathrm { AgBr } {/tex}(s) Sandmeyer's reaction

A-(q), B-(s), C-(p), D-(r)

B

A-(q), B-(r), C-(p), D-(s)

C

A-(r), B-(p), C-(s), D-(q)

D

A-(s), B-(r), C-(p), D-(q)

Explanation

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Q 10. The electrons, identified by quantum numbers {tex}\mathrm { n }{/tex} and {tex}\mathrm l{/tex}{tex} ( \mathrm { i } )\ \mathrm { n } = 4,\mathrm l = 1\\ ( \mathrm { ii } ) \mathrm { n } = 4 , \mathrm { l } = 0 \\ (\mathrm { iii}) \mathrm { n } = 3,\mathrm l = 2\\ (\mathrm { iv }) \mathrm { n } = 3,\mathrm { l } = 1 {/tex} can be placed in order of increasing energy, from the lowest to highest, as

{tex}\mathrm{ ( i v ) < ( i i ) < ( iii ) < ( i )} {/tex}

B

{tex}\mathrm{ ( i i ) < ( i v ) < ( i ) < ( i i i )} {/tex}

C

{tex}\mathrm{(i) < ( { iii } ) < ( { ii } ) < ( { iv } )} {/tex}

D

{tex}\mathrm{ ( { iii } ) < ( i ) < ( i v ) < ( i i ) }{/tex}

Explanation

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Q 11. In an adiabatic process, no transfer of heat takes place between system and surroundings. Choose the correct option for free expansion of an ideal gas under adiabatic condition from the following.

A

{tex} \mathrm { q } = 0 , \Delta \mathrm { T } \neq 0 , \mathrm { w } = 0 {/tex}

B

{tex} \mathrm { q } \neq 0 , \Delta \mathrm { T } = 0 , \mathrm { w } = 0 {/tex}

{tex} \mathrm { q } = 0 , \Delta \mathrm { T } = 0 , \mathrm { w } = 0 {/tex}

D

{tex} \mathrm { q } = 0 , \Delta \mathrm { T } < 0 , \mathrm { w } \neq 0 {/tex}

Explanation

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Q 12. In which of the following cases, the stability of two oxidation states is correctly represented

A

{tex} \mathrm { Ti } ^ { 3 + } > \mathrm { Ti } ^ { 4 + } {/tex}

{tex} \mathrm { Mn } ^ { 2 + } > \mathrm { Mn } ^ { 3 + } {/tex}

C

{tex} \mathrm { Fe } ^ { 2 + } > \mathrm { Fe } ^ { 3 + } {/tex}

D

{tex} \mathrm { Cu } ^ { + } > \mathrm { Cu } ^ { 2 + } {/tex}

Explanation

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Q 13. Which is not the disproportionation reaction?

A

{tex} 3 \mathrm { H } _ { 3 } \mathrm { PO } _ { 2 } \longrightarrow 2 \mathrm { H } _ { 3 } \mathrm { PO } _ { 2 } + \mathrm { PH } _ { 3 } {/tex}

B

{tex} \mathrm { HCHO } + \mathrm { OH } ^ { - } \longrightarrow \mathrm { HCOO } ^ { - } + \mathrm { CH } _ { 3 } \mathrm { OH } {/tex}

{tex} \mathrm { NH } _ { 4 } \mathrm { NO } _ { 3 } \longrightarrow \mathrm { N } _ { 2 } \mathrm { O } + 2 \mathrm { H } _ { 2 } \mathrm { O } {/tex}

D

{tex} 3 \mathrm { Cl } _ { 2 } + 6 \mathrm { OH } ^ { - } \longrightarrow 5 \mathrm { Cl } ^ { - } + \mathrm { ClO } _ { 3 } ^ { - } + 3 \mathrm { H } _ { 2 } \mathrm { O } {/tex}

Explanation

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Q 14. The major organic product in the reaction, {tex} \mathrm { CH } _ { 3 } - \mathrm { O } - \mathrm { CH } \left( \mathrm { CH } _ { 3 } \right) _ { 2 } + \mathrm { HI } \rightarrow {/tex} Product is

A

{tex} \mathrm { ICH } _ { 2 } \mathrm { OCH } \left( \mathrm { CH } _ { 3 } \right) _ { 2 } {/tex}

B

{tex} \mathrm { CH } _ { 3 } \mathrm { I } + \left( \mathrm { CH } _ { 3 } \right) _ { 2 } \mathrm { CHOH } {/tex}

D

{tex} \mathrm { CH } _ { 3 } \mathrm { OH } + \left( \mathrm { CH } _ { 3 } \right) _ { 2 } \mathrm { CHI } {/tex}

Explanation

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Q 15. The rate constant of a zero order reaction is {tex} 2.0 \times 10 ^ { - 2 } \mathrm { mol } \mathrm { L } ^ { - 1 } \mathrm { s } ^ { - 1 } {/tex}. If the concentration of the reactant after {tex}25{/tex} seconds is {tex} 0.5 \mathrm { M } {/tex}. What is the initial concentration?

A

{tex} 0.5 \mathrm { M } {/tex}

B

{tex} 1.25 \mathrm { M } {/tex}

C

{tex} 12.5 \mathrm { M } {/tex}

{tex} 1.0 \mathrm { M } {/tex}

Explanation

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Q 16. The correct order of solubility in water for {tex}\mathrm {He, Ne, Ar, Kr, Xe}{/tex} is

A

{tex} \mathrm { He } > \mathrm { Ne } > \mathrm { Ar } > \mathrm { Kr } > \mathrm { Xe } {/tex}

{tex} \mathrm { Xe } > \mathrm { Kr } > \mathrm { Ar } > \mathrm { Ne } > \mathrm { He } {/tex}

C

{tex}\mathrm{N e > A r > K r > H e> X e} {/tex}

D

{tex}\mathrm{ A r > N e > H e > K r > X e} {/tex}

Explanation

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Q 17. The de Broglie wavelength of a car of mass {tex} 1000 \mathrm { kg } {/tex} and velocity {tex} 36 \mathrm { km } / \mathrm { hr } {/tex} is :

A

{tex} 6.626 \times 10 ^ { - 34 } \mathrm { m } {/tex}

{tex} 6.626 \times 10 ^ { - 38 } \mathrm { m } {/tex}

C

{tex} 6.626 \times 10 ^ { - 31 } \mathrm { m } {/tex}

D

{tex} 6.626 \times 10 ^ { - 30 } \mathrm { m } {/tex}

Explanation

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Q 18. The correct IUPAC name for

A

5-Methyl-4-(1'-2'-dimethylpropyl) heptane

B

3-Methyl-4-(1',2'-dimethylpropyl) heptane

2,3,5-Trimethyl-4-propylheptane

D

4-Propyl-2,3,5-trimethylpeptane

Explanation

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Q 19. Which of the following shows iso-structural species?

A

{tex} \mathrm { NH } _ { 4 } ^ { + } {/tex} and {tex} \mathrm { NH } _ { 2 } ^ { - } {/tex}

B

{tex} \mathrm { CH } _ { 3 } ^ { - } {/tex} and {tex} \mathrm { CH } _ { 3 } ^ { + } {/tex}

{tex} \mathrm { SO } _ { 4 } ^ { 2 - } , \mathrm { PO } _ { 4 } ^ { 3 - } {/tex} and {tex} \left[ \mathrm { BF } _ { 4 } \right] ^ { - } {/tex}

D

{tex} \mathrm { NH } _ { 4 } ^ { + } {/tex} and {tex} \mathrm { NH } _ { 3 } {/tex}

Explanation

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Q 20. When dihydroxyacetone reacts with {tex} \mathrm { HIO } _ { 4 } , {/tex} the product is/are:

A

{tex} \mathrm { HCHO } {/tex}

B

{tex}\mathrm {HCOOH}{/tex}

C

{tex}\mathrm {HCHO}{/tex} and {tex}\mathrm {HCOOH}{/tex}

{tex} \mathrm { HCHO } {/tex} and {tex} \mathrm { CO } _ { 2 } {/tex}

Explanation

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Q 21. Consider the reactions
{tex} \mathrm {(A)\ H } _ { 2 } \mathrm { O } _ { 2 } + 2 \mathrm { HI } \rightarrow \mathrm { I } _ { 2 } + 2 \mathrm { H } _ { 2 } \mathrm { O } {/tex}
{tex} \mathrm {(B)\ HOCl } + \mathrm { H } _ { 2 } \mathrm { O } _ { 2 } \rightarrow \mathrm { H } _ { 3 } \mathrm { O } ^ { + } + \mathrm { Cl } ^ { - } + \mathrm { O } _ { 2 } {/tex}
Which of the following statements is correct about {tex} \mathrm { H } _ { 2 } \mathrm { O } _ { 2 } {/tex} with reference to these reactions?
Hydrogen peroxide is _________.

A

an oxidising agent in both (A) and (B)

an oxidising agent in (A) and reducing agent in (B)

C

a reducing agent in (A) and oxidising agent in (B)

D

a reducing agent in both (A) and (B)

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Q 22. A certain compound (X) when treated with copper sulphate solution yields a brown precipitate. On adding hypo solution, the precipitate turns white. The compound is

A

{tex} \mathrm { K } _ { 2 } \mathrm { CO } _ { 3 } {/tex}

{tex} \mathrm { KI } {/tex}

C

{tex} \mathrm { KBr } {/tex}

D

{tex} \mathrm { K } _ { 3 } \mathrm { PO } _ { 4 } {/tex}

Explanation

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Q 23. Consider the following reactions:
{tex} \mathrm {(i)\ H } ^ { + } ( \mathrm { aq } ) + \mathrm { OH } ^ { - } ( \mathrm { aq } ) \rightarrow \mathrm { H } _ { 2 } \mathrm { O } ( \mathrm { l } ) , \\ \Delta \mathrm { H } = - \mathrm { X } _ { 1 } \mathrm { kJ } \mathrm { mol } ^ { - 1 }\\ \mathrm {(ii) } \mathrm { H } _ { 2 } ( \mathrm { g } ) + \frac { 1 } { 2 } \mathrm { O } _ { 2 } ( \mathrm { g } ) \rightarrow \mathrm { H } _ { 2 } \mathrm { O } ( \mathrm { l } )\\\Delta \mathrm { H } = - \mathrm { X } _ { 2 } \mathrm { kJ } \mathrm { mol } ^ { - 1 }\\ \mathrm { (iii) } \mathrm { CO } _ { 2 } ( \mathrm { g } ) + \mathrm { H } _ { 2 } \rightarrow \mathrm { CO } ( \mathrm { g } ) + \mathrm { H } _ { 2 } \mathrm { O }\\ \Delta \mathrm { H } = - \mathrm { X } _ { 3 } \mathrm { kJ } \mathrm { mol } ^ { - 1 } \\ \text { (iv) } \mathrm { C } _ { 2 } \mathrm { H } _ { 2 } ( \mathrm { g } ) + \frac { 5 } { 2 } \mathrm { O } _ { 2 } ( \mathrm { g } ) \rightarrow 2 \mathrm { CO } _ { 2 } ( \mathrm { g } ) + \mathrm { H } _ { 2 } \mathrm { O } ( \mathrm { l } ) \\ \Delta \mathrm { H } = + 4 \mathrm { X } _ { 4 } \mathrm { kJ } \mathrm { mol } ^ { - 1 } {/tex}
Enthalpy of formation of {tex}\mathrm {H_2O}_{\mathrm {(l)}}{/tex} is

A

{tex} \mathrm {+ X _ { 3 } k J m o l ^ { - 1 }} {/tex}

B

{tex} - \mathrm { X } _ { 4 } \mathrm { kJ } \mathrm { mol } ^ { - 1 } {/tex}

C

{tex} + \mathrm { X } _ { 1 } \mathrm { kJ } \mathrm { mol } ^ { - 1 } {/tex}

{tex} - \mathrm { X } _ { 2 } \mathrm { kJ } \mathrm { mol } ^ { - 1 } {/tex}

Explanation

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Q 24. Which of the following possesses a sp-carbon in its structure?

A

{tex} \mathrm { CH } _ { 2 } = \mathrm { CCI } - \mathrm { CH } = \mathrm { CH } _ { 2 } {/tex}

B

{tex} \mathrm { CCI } _ { 2 } = \mathrm { CCl } _ { 2 } {/tex}

{tex} \mathrm { CH } _ { 2 } = \mathrm { C } = \mathrm { CH } _ { 2 } {/tex}

D

{tex} \mathrm { CH } _ { 2 } = \mathrm { CH } - \mathrm { CH } = \mathrm { CH } _ { 2 } {/tex}

Explanation

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Q 25. A balloon has maximum capacity of {tex} 20 \mathrm { L } {/tex}. At one atmospheric pressure {tex} 10 \mathrm { L } {/tex} of air is filled in the balloon. It will burst when pressure is (assuming isothermal condition)

A

{tex} > 0.5 \mathrm { atm} {/tex}

{tex} < 0.5 \mathrm { atm } {/tex}

C

{tex} = 0.5 \mathrm { atm } {/tex}

D

{tex} \geq 0.5 \mathrm {atm} {/tex}

Explanation