For the electrochemical cell, M | M⁺ || X^- | X, ${\mathrm{E}}^{°}$(M⁺| M) = 0.44 V and ${\mathrm{E}}^{°}$(X | X^-) = 0.33 V. From this data one can deduce that

• M + X^- $\to$M^- + X^- is the spontateous reaction.

• M⁺ + X^- $\to$M + X is the spontaneous reaction.

• E_cell = 0.77 V

• E_cell = -0.77V

Assertion : Magnesium is extracted by the electrolysis of fused mixture of MgCl₂, NaCl and CaCl₂.

Reason : Calcium chloride acts as a reducing agent.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion : Zinc displaces copper from copper sulphate solution.

Reason : The ${\mathrm{E}}^{°}$of zinc is= 0.76 V and that of copper is + 0.34 V.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Which of the following does not conduct electricity ?

• Fused NaCl

• Solid NaCl

• Brine solution

• Copper

When a quantity of electricity is passed through CusO₄ solution , 0.16 g of copper gets deposited .If the same quantity of electricity is passed through acidulated water , then the volume of H₂ liberated at STP will be :

[Given : atomic weight of Cu = 64]

• 10 cm³

• 56 cm³

• 604 cm³

• 8.0 cm³

Which one of the following condition will increase the voltage of the cell represented by the equation ?

Cu (s) + 2Ag⁺ (aq) $\rightleftharpoons$ Cu²⁺ (aq) + 2Ag (s)

• Increase in the dimension of Cu electrode

• Increase in the dimension of Ag electrode

• Increase in the concentration of Cu²⁺ ion

• Increase in the concentration of Ag⁺ ions

357.

Which of the following electrolyte will have maximum flocculation value for Fe(OH)₃ sol ?

• NaCl

• Na₂S

• (NH₄)₃PO₄

• K₂SO₄

The time period to coat a metal surface of 80 cm² with 5 x 10^-3 cm thick layer of silver (density 1.05 g cm^-3) with the passage of 3 A current through a silver nitrate solution is

• 115 sec

• 125 sec

• 135 sec

• 145 sec

Ni/Ni²⁺ [1.0 M] || Au³⁺ [1.0 M]/Au (where E° for Ni²⁺/Ni  is -0.25 V E° for Au³⁺/Au is 0.150 V)

Whar is the emf of the cell ?

• + 0.4 V

• - 1.75 V

• + 1.25 V

• + 1.75 V

The specific conductance of a N/ 10 KCl at 25°C is 0.0112 ohm^-1cm^-1.The resistance of cell containing solution at the same temperature was found to be 55 ohm. The cell constant will be

• 6.16 cm^-1

• 0.616 cm^-1

• 0.0616 cm^-1

• 616 cm^-1