The equivalent conductance at infinite dilution of a weak acid such as HF

• can be determined by extrapolation of measurements on dilute solutions of HCl, HBr and HI

• can be determined by measurement on very dilute HF solutions

• can best be determined from measurements on dilute solutions of NaF, NaCl and HCl

• is an undefined quantity

The number of Faradays needed to reduce 4 g equivalents of Cu²⁺to Cu metal will be

• 1

• 2

• 1/2

• 4

Which one of the following cells can convert chemical energy of H₂ and O₂ directly into electrical energy?

• Mercury cell

• Daniell cell

• Fuel cel

• Lead storage cell

394.

$$\begin{gathered} \mathrm{For} \mathrm{the} \mathrm{following} \mathrm{cell} \mathrm{reaction}, \\ \mathrm{Ag}| {\mathrm{Ag}}^{+}| \mathrm{AgCl}| {\mathrm{Cl}}^{⊝}| {\mathrm{Cl}}_2, \mathrm{Pt} \\ ∆{\mathrm{G}}_{\mathrm{f}}^{°}\left(\mathrm{AgCl}\right)= -109 \mathrm{kJ}/\mathrm{mol} \\ ∆{\mathrm{G}}_{\mathrm{f}}^{°}\left({\mathrm{Cl}}^{⊝}\right)= -129 \mathrm{kJ}/\mathrm{mol} \\ ∆{\mathrm{G}}_{\mathrm{f}}^{°}\left({\mathrm{Ag}}^{+}\right)= 78 \mathrm{kJ}/\mathrm{mo}/ \end{gathered}$$

E$°$ of the cell is

• - 0.60 V

• 0.60 V

• 6.0 V

• None of these

At 25$°$C, the molar conductances at infinite dilution for the strong electrolytes NaOH, NaCl and BaCl₂ are 248 $\times$10^-4, 126 x 10^-4 and 280 x 10^-4 Sm² mol^-1 respectively, ${\mathrm{\lambda }}_{\mathrm{m}}^{\infty }$  Ba(OH)₂ in Sm² mol^-1 is

• 52.4 $\times$ 10^-4

• 524 $\times {10}^{-4}$

• 402 $\times {10}^{-4}$

• 262 $\times {10}^{-4}$

The molar conductivities of KCl, NaCl and KNO₃ are 152, 128 and 111 S cm²mol^-1 respectively. What is the molar conductivity of NaNO₃?

• 101 S cm²mol^-1 

• 87 S cm²mol^-1 

• -101 S cm²mol^-1 

• -39 S cm²mol^-1 

The electrochemical cell stops working after sometime because

• electrode potential of both the electrodes becomes zero

• electrode potential of both the electrodes becomes equal

• one of the electrodes is eaten away

• the cell reaction gets reversed

The amount of electricity required to produce one mole of copper from copper sulphate solution will be

• 1 F

• 2.33 F

• 2 F

• 1.33 F

How long (in hours) must a current of 5.0 A be maintained to electroplate 60 g of calcium from molten CaCl₂ ?

• 27 h

• 8.3 h

• 11 h

• 16 h

For strong electrolytes the plot of molar conductance vs $\sqrt{\mathrm{C}}$ is

• parabolic

• linear

• sinusoidal

• circular