At 298 K, a certain buffer solution contains equal concentrations of \(X^-\) and HX, Kb for \(X^-\) is \(10^{-10}\). What is the pH of this buffer solution?
1. 4
2. 6
3. 2
4. 10
1. 4
2. 6
3. 2
4. 10
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The correct IUPAC name of the following compound is :
1. 3-methyl-5-ethylheptane
2. 3-ethyl-5-methylheptane
3. 3,5-diethylhexane
4. 2,4-diethylhexane
1. 3-methyl-5-ethylheptane
2. 3-ethyl-5-methylheptane
3. 3,5-diethylhexane
4. 2,4-diethylhexane
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73. The following two reactions give the same foul smelling product Z.
X and Z, respectively, are :
1. \(X = AgCN; Z = C_2H_5CN\)
2. \(X = KCN; Z = C_2H_5CN\)
3. \(X = KCN; Z = C_2H_5NC\)
4. \(X = AgCN; Z = C_2H_5NC\)
X and Z, respectively, are :
1. \(X = AgCN; Z = C_2H_5CN\)
2. \(X = KCN; Z = C_2H_5CN\)
3. \(X = KCN; Z = C_2H_5NC\)
4. \(X = AgCN; Z = C_2H_5NC\)
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Mixture of chloroform and acetone forms a solution with negative deviation from Raoult's law due to:
| 1. | increase in escaping tendency of molecules of each component. |
| 2. | repulsive forces. |
| 3. | stronger intermolecular forces between chloroform molecules than those between chloroform and acetone molecules. |
| 4. | formation of hydrogen bonding between acetone and chloroform. |
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Identify the correct statements:
Choose the correct answer from the options given below:
1. A and B only
2. A, D and E only
3. A, B and C only
4. A and C only
| A. | The molality of 2.5 g of ethanoic acid (Molar mass : 60 g mol-1) in 75 g of benzene solution is 0.556 m. |
| B. | The molarity of a solution containing 5 g of NaOH (molar mass : 40 g mol-1) in 450 mL of solution is 0.278 M at 298 K. |
| C. | Aquatic species are more comfortable in cold water. |
| D. | The solubility of gas increases with decrease in pressure. |
| E. | For a binary mixture of A and B, the number of moles of A and B are nA and nB respectively. The mole fraction of B will be \(x_B = \frac{n_A}{n_A + n_B}\). |
Choose the correct answer from the options given below:
1. A and B only
2. A, D and E only
3. A, B and C only
4. A and C only
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Identify the incorrect statement from the following :
| 1. | ECl3 (E = B and Al) is a monomer when E = B and a dimer when E = Al. |
| 2. | The order of catenation property of Group 14 elements is C ≫ Si > Ge ≈ Sn. |
| 3. | Oxygen exhibits only -2 oxidation state. |
| 4. | Carbon has the ability to form π-π multiple bond with itself. |
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The correct formal charges on oxygen atoms numbered 2, 1 and 3 respectively are:
1. − 1, 0, + 1
2. 0, 0, 0
3. 0, + 1, − 1
4. + 1, 0, − 1
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At a certain temperature, T (K), during a process, 500 J is absorbed by the system and work of 200 J is done by the system. Then change in internal energy of the system is:
1. 500 J
2. 400 J
3. 300 J
4. 700 J
1. 500 J
2. 400 J
3. 300 J
4. 700 J
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Consider the following reaction:
\(2A (g) + B (g) \rightarrow 2D (g)\)
\(\Delta U^{\ominus} = -10\text{ kJ mol}^{-1}\) and \(\Delta S^{\ominus} = -44\text{ J K}^{-1}\) at \(298\text{ K}\).
Identify the correct option with \(\Delta G^{\ominus}\) for the reaction and spontaneity of the reaction at \(298\text{ K}\).
(Given: \(R = 8.31\text{ J mol}^{-1}\text{K}^{-1}\))
1. \(-0.63568\text{ kJ mol}^{-1}\), spontaneous
2. \(+0.63568\text{ kJ mol}^{-1}\), non-spontaneous
3. \(-1.635\text{ kJ mol}^{-1}\), spontaneous
4. \(+1.635\text{ kJ mol}^{-1}\), non-spontaneous
\(2A (g) + B (g) \rightarrow 2D (g)\)
\(\Delta U^{\ominus} = -10\text{ kJ mol}^{-1}\) and \(\Delta S^{\ominus} = -44\text{ J K}^{-1}\) at \(298\text{ K}\).
Identify the correct option with \(\Delta G^{\ominus}\) for the reaction and spontaneity of the reaction at \(298\text{ K}\).
(Given: \(R = 8.31\text{ J mol}^{-1}\text{K}^{-1}\))
1. \(-0.63568\text{ kJ mol}^{-1}\), spontaneous
2. \(+0.63568\text{ kJ mol}^{-1}\), non-spontaneous
3. \(-1.635\text{ kJ mol}^{-1}\), spontaneous
4. \(+1.635\text{ kJ mol}^{-1}\), non-spontaneous
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Select the reagents that reduce nitriles to primary amines:
Choose the correct answer from the options given below:
1. A, C and D only
2. A, B and C only
3. B, D and E only
4. A, D and E only
| A. | (i) \(LiAlH_4\); (ii) \(H_2O\) |
| B. | \(Sn + HCl\) |
| C. | \(H_2/Ni\) |
| D. | \(Na(Hg)/C_2H_5OH\) |
| E. | \(Br_2/aq. NaOH\) |
Choose the correct answer from the options given below:
1. A, C and D only
2. A, B and C only
3. B, D and E only
4. A, D and E only
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