Q52. Number of molecules having bond order 2 from the following molecules is $\_\_\_\_$ $\mathrm { C } _ { 2 } , \mathrm { O } _ { 2 } , \mathrm { Be } _ { 2 } , \mathrm { Li } _ { 2 } , \mathrm { Ne } _ { 2 } , \mathrm {~N} _ { 2 } , \mathrm { He } _ { 2 }$

Q52. The total number of species from the following in which one unpaired electron is present, is $\_\_\_\_$ $\mathrm { N } _ { 2 } , \mathrm { O } _ { 2 } , \mathrm { C } _ { 2 } ^ { - } , \mathrm { O } _ { 2 } ^ { - } , \mathrm { O } _ { 2 } ^ { 2 - } , \mathrm { H } _ { 2 } ^ { + } , \mathrm { CN } ^ { - } , \mathrm { He } _ { 2 } ^ { + }$

Q52. Total number of electrons present in ( $\pi ^ { * }$ ) molecular orbitals of $\mathrm { O } _ { 2 } , \mathrm { O } _ { 2 } { } ^ { + }$and $\mathrm { O } _ { 2 } ^ { - }$is $\_\_\_\_$ .

Q53. The enthalpy of formation of ethane $\left( \mathrm { C } _ { 2 } \mathrm { H } _ { 6 } \right)$ from ethylene by addition of hydrogen where the bond-energies of $\mathrm { C } - \mathrm { H } , \mathrm { C } - \mathrm { C } , \mathrm { C } = \mathrm { C } , \mathrm { H } - \mathrm { H }$ are $414 \mathrm {~kJ} , 347 \mathrm {~kJ} , 615 \mathrm {~kJ}$ and 435 kJ respectively is $\quad \mathrm { kJ }$

Q53. Three moles of an ideal gas are compressed isothermally from 60 L to 20 L using constant pressure of 5 atm . Heat exchange Q for the compression is - $\_\_\_\_$ Lit. atm.

Q53. In the lewis dot structure for $\mathrm { NO } _ { 2 } ^ { - }$, total number of valence electrons around nitrogen is $\_\_\_\_$

Q53. Combustion of 1 mole of benzene is expressed at $\mathrm { C } _ { 6 } \mathrm { H } _ { 6 } ( \mathrm { l } ) + \frac { 15 } { 2 } \mathrm { O } _ { 2 } ( \mathrm {~g} ) \rightarrow 6 \mathrm { CO } _ { 2 } ( \mathrm {~g} ) + 3 \mathrm { H } _ { 2 } \mathrm { O } ( \mathrm { l } )$. The standard enthalpy of combustion of 2 mol of benzene is $- ^ { \prime } x ^ { \prime } \mathrm { kJ } . x =$ $\_\_\_\_$ Given: 1. standard Enthalpy of formation of 1 mol of $\mathrm { C } _ { 6 } \mathrm { H } _ { 6 } ( \mathrm { l } )$, for the reaction 6 C (graphite) $+ 3 \mathrm { H } _ { 2 } ( \mathrm {~g} ) \rightarrow \mathrm { C } _ { 6 } \mathrm { H } _ { 6 } ( \mathrm { l } )$ is $48.5 \mathrm {~kJ} \mathrm {~mol} ^ { - 1 }$. 2. Standard Enthalpy of formation of 1 mol of $\mathrm { CO } _ { 2 } ( \mathrm {~g} )$, for the reaction C (graphite) $+ \mathrm { O } _ { 2 } ( \mathrm {~g} ) \rightarrow \mathrm { CO } _ { 2 } ( \mathrm {~g} )$ is $- 393.5 \mathrm {~kJ} \mathrm {~mol} ^ { - 1 } .3$. Standard and Enthalpy of formation of 1 mol of $\mathrm { H } _ { 2 } \mathrm { O } ( \mathrm { l } )$, for the reaction $\mathrm { H } _ { 2 } ( \mathrm {~g} ) + \frac { 1 } { 2 } \mathrm { O } _ { 2 } ( \mathrm {~g} ) \rightarrow \mathrm { H } _ { 2 } \mathrm { O } ( \mathrm { l } )$ is $- 286 \mathrm {~kJ} \mathrm {~mol} ^ { - 1 }$.

Q53. An ideal gas, $\overline { \mathrm { C } } _ { \mathrm { v } } = \frac { 5 } { 2 } \mathrm { R }$, is expanded adiabatically against a constant pressure of 1 atm untill it doubles in volume. If the initial temperature and pressure is 298 K and 5 atm , respectively then the final temperature is $\_\_\_\_$ K (nearest integer). [ $\overline { \mathrm { C } } _ { \mathrm { v } }$ is the molar heat capacity at constant volume]

Q53. An amine ( X ) is prepared by ammonolysis of benzyl chloride. On adding p -toluenesulphonyl chloride to it the solution remains clear. Molar mass of the amine ( X ) formed is $\_\_\_\_$ gmol $^ { - 1 }$. (Given molar mass in $\left. \mathrm { gmol } ^ { - 1 } \mathrm { C } : 12 , \mathrm { H } : 1 , \mathrm { O } : 16 , \mathrm {~N} : 14 \right)$
Q54.For the reaction at $298 \mathrm {~K} , 2 \mathrm {~A} + \mathrm { B } \rightarrow \mathrm { C } . \Delta \mathrm { H } = 400 \mathrm {~kJ} \mathrm {~mol} ^ { - 1 }$ and $\Delta \mathrm { S } = 0.2 \mathrm {~kJ} \mathrm {~mol} ^ { - 1 } \mathrm {~K} ^ { - 1 }$. The reaction will become spontaneous above K .

53. (55) & 54. (32) & 55. (5) & 56. (1) \hline 61. (1) & 62. (1) & 63. (1) & 64. (2) \hline 69. (4) & 70. (4) & 71. (4) & 72. (2) \hline 77. (3) & 78. (4) & 79. (1) & 80. (1) \hline 85. (55) & 86. (7) & $87 . ( 96 )$ & 88. (16) \hline \end{tabular}

Q53. $\Delta _ { \text {vap } } \mathrm { H } ^ { \ominus }$ for water is $+ 40.79 \mathrm {~kJ} \mathrm {~mol} ^ { - 1 }$ at 1 bar and $100 ^ { \circ } \mathrm { C }$. Change in internal energy for this vapourisation under same condition is $\mathrm { kJmol } ^ { - 1 }$. (Integer answer) (Given $\mathrm { R } = 8.3 \mathrm { JK } ^ { - 1 } \mathrm {~mol} ^ { - 1 }$ )

Q53. When equal volume of 1 MHCl and $1 \mathrm { MH } _ { 2 } \mathrm { SO } _ { 4 }$ are separately neutralised by excess volume of 1 M NaOH solution. $x$ and $y \mathrm {~kJ}$ of heat is liberated respectively. The value of $y / x$ is $\_\_\_\_$

Q53. When $\Delta \mathrm { H } _ { \text {vap } } = 30 \mathrm {~kJ} / \mathrm { mol }$ and $\Delta \mathrm { S } _ { \text {vap } } = 75 \mathrm {~J} \mathrm {~mol} ^ { - 1 } \mathrm {~K} ^ { - 1 }$, then the temperature of vapour, at one atmosphere is $\_\_\_\_$ K.
Q54. [Figure]
In the given TLC, the distance of spot $\mathrm { A } \& \mathrm {~B}$ are $5 \mathrm {~cm} \& 7 \mathrm {~cm}$, from the bottom of TLC plate, respectively. $\mathrm { R } _ { \mathrm { f } }$ value of B is $x \times 10 ^ { - 1 }$ times more than A . The value of $x$ is $\_\_\_\_$ .

Q54. Only 2 mL of $\mathrm { KMnO } _ { 4 }$ solution of unknown molarity is required to reach the end point of a titration of 20 mL of oxalic acid ( 2 M ) in acidic medium. The molarity of $\mathrm { KMnO } _ { 4 }$ solution should be

Q54. The total number of 'sigma' and 'Pi' bonds in2-oxohex-4-ynoic acid is $\_\_\_\_$

Q54. The heat of combustion of solid benzoic acid at constant volume is - 321.30 kJ at $27 ^ { \circ } \mathrm { C }$. The heat of combustion at constant pressure is $( - 321.30 - x \mathrm { R } ) \mathrm { kJ }$, the value of $x$ is $\_\_\_\_$ .

Q54. Using the given figure, the ratio of $\mathrm { R } _ { f }$ values of sample A and sample C is $x \times 10 ^ { - 2 }$. Value of $x$ is $\_\_\_\_$
[Figure]
Fig: Paper chromatography of Samples

Q54. The major product of the following reaction is $P . \mathrm { CH } _ { 3 } \mathrm { C } = \mathrm { C } - \mathrm { CH } _ { 3 } \xrightarrow [ \substack { \text { (ii) } \text { dil. } \mathrm { KMnO } _ { 4 } \\ 273 \mathrm {~K} } ] { \text { (i) } \mathrm { Na } / \mathrm { ing } ^ { 2 } \mathrm { NH } _ { 3 } }$ " Number of oxygen atoms present in product ' P ' is $\_\_\_\_$ (nearest integer)

Q54.
The number of optical isomers in following compound is: $\_\_\_\_$ [Figure]

Q54. Total number of optically active compounds from the following is $\_\_\_\_$ [Figure] [Figure]
$$\mathrm { CH } _ { 3 } - \mathrm { CH } _ { 2 } - \mathrm { CH } _ { 2 } - \mathrm { CH } _ { 2 } - \mathrm { OH } \text {, }$$
[Figure] $\mathrm { CH } _ { 3 } - \mathrm { CH } _ { 2 } - \mathrm { CH } _ { 2 } - \mathrm { CH } _ { 2 } - \mathrm { Cl }$, $\left( \mathrm { CH } _ { 3 } \right) _ { 2 } \mathrm { CH } - \mathrm { CH } _ { 2 } - \mathrm { CH } _ { 2 } - \mathrm { Cl }$

Q54. The heat of solution of anhydrous $\mathrm { CuSO } _ { 4 }$ and $\mathrm { CuSO } _ { 4 } \cdot 5 \mathrm { H } _ { 2 } \mathrm { O }$ are $- 70 \mathrm {~kJ} \mathrm {~mol} ^ { - 1 }$ and $+ 12 \mathrm {~kJ} \mathrm {~mol} ^ { - 1 }$ respectively. The heat of hydration of $\mathrm { CuSO } _ { 4 }$ to $\mathrm { CuSO } _ { 4 } \cdot 5 \mathrm { H } _ { 2 } \mathrm { O }$ is $- x \mathrm {~kJ}$. The value of $x$ is $\_\_\_\_$ (nearest integer).

Q55. The number of different chain isomers for $\mathrm { C } _ { 7 } \mathrm { H } _ { 16 }$ is

Q55. 2.7 kg of each of water and acetic acid are mixed. The freezing point of the solution will be $- x ^ { \circ } \mathrm { C }$. Consider the acetic acid does not dimerise in water, nor dissociates in water. $x =$ $\_\_\_\_$ (nearest integer) [Given: Molar mass of water $= 18 \mathrm {~g} \mathrm {~mol} ^ { - 1 }$, acetic acid $= 60 \mathrm {~g} \mathrm {~mol} ^ { - 1 } \mathrm {~K} _ { \mathrm { f } } \mathrm { H } _ { 2 } \mathrm { O } : 1.86 \mathrm {~K} \mathrm {~kg} \mathrm {~mol} ^ { - 1 } \mathrm {~K} _ { \mathrm { f } }$ acetic acid: $3.90 \mathrm {~K} \mathrm {~kg} \mathrm {~mol} ^ { - 1 }$ freezing point: $\mathrm { H } _ { 2 } \mathrm { O } = 273 \mathrm {~K}$, acetic acid $= 290 \mathrm {~K}$ ]

Q55. An artificial cell is made by encapsulating 0.2 M glucose solution within a semipermeable membrane. The osmotic pressure developed when the artificial cell is placed within a 0.05 M solution of NaCl at 300 K is $\_\_\_\_$ $\times 10 ^ { - 1 }$ bar. (nearest integer). [Given : $\mathrm { R } = 0.083 \mathrm { Lbarmol } ^ { - 1 } \mathrm {~K} ^ { - 1 }$ ] Assume complete dissociation of NaCl

Q55. Considering acetic acid dissociates in water, its dissociation constant is $6.25 \times 10 ^ { - 5 }$. If 5 mL of acetic acid is dissolved in 1 litre water, the solution will freeze at $- x \times 10 ^ { - 2 } { } ^ { \circ } \mathrm { C }$, provided pure water freezes at $0 ^ { \circ } \mathrm { C } . x =$
$$\begin{aligned} & \left( \mathrm { K } _ { f } \right) _ { \text {water } } = 1.86 \mathrm {~K} \mathrm {~kg} \mathrm {~mol} ^ { - 1 } . \\ & \text { density of acetic acid is } 1.2 \mathrm {~g} \mathrm {~mol} ^ { - 1 } . \end{aligned}$$
$\_\_\_\_$ . (Nearest integer) Given : molar mass of water $= 18 \mathrm {~g} \mathrm {~mol} ^ { - 1 }$. Acetic acid dissociates as molar mass of acetic acid $= 60 \mathrm { gmol } ^ { - 1 }$.
$$\text { density of water } = 1 \mathrm {~g} \mathrm {~cm} ^ { - 3 }$$
$\mathrm { CH } _ { 3 } \mathrm { COOH } \rightleftharpoons \mathrm { CH } _ { 3 } \mathrm { COO } ^ { \ominus } + \mathrm { H } ^ { \oplus }$