The maximum work which can be obtained from a Daniel cell \(Zn_{(s)}\ |\ Zn^{+2}_{(aq)}\ || Cu^{+2}_{(aq)}\ |\ Cu_{(s)}\) is:

\(E^o_{Zn^{2+}/Zn}\)	−0.76 V
\(E^o_{Cu^{2+}/Cu}\)	0.34 V

1. +106.15 kJ

2. -212.3 kJ

3. -424.6 kJ

4. +212.3 kJ

CuSO₄ solution is treated separately with KCl and KI. In which case, Cu⁺² will be reduced to ${\mathrm{Cu}}^{\oplus }$ ?

(1) with KCl

(2) with KI

(3) with KCl and KI both

(4) None of these

How many coulombs are required to oxidise 1 mol H₂O₂ to O₂ ?

(1) 9.65 X 10⁴ C

(2) 9.3 X 10⁴ C

(3) 1.93 X 10⁵ C

(4) 19.3 X 10² C

The quantity of electricity required to reduce 12.3 g of nitrobenzene to aniline with 50 % current efficiency is:

1. 1 F

2. 0.6 F

3. 0.5 F

4. 1.2 F

Electrolysis of hot aqueous solution of NaCl gives NaClO₄ as-

$\mathrm{NaCl} +\hspace{0.17em}4{\mathrm{H}}_2\mathrm{O} \stackrel{ }{\to }{\mathrm{NaClO}}_4 + 4{\mathrm{H}}_2$

How many faraday are required to obtain 1000 g of sodium perchlorate ?

(1) 66 F

(2) 122.5 F

(3) 15.13 F

(4) 1.86 F

The cell reaction of micro electrochemical cell formed during rusting of iron is:-

1.  ${\mathrm{O}}_2\left(\mathrm{g}\right) + 4{\mathrm{H}}^{\oplus }\left(\mathrm{aq}\right) + 4{\mathrm{e}}^{-} \to 2{\mathrm{H}}_2\mathrm{O} \left(\mathrm{l}\right)$

2. $4{\mathrm{Fe}}^{+2}\left(\mathrm{aq}\right) + {\mathrm{O}}_2\left(\mathrm{g}\right) + 2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right) \to 4\mathrm{FeO} + 4{\mathrm{H}}^{\oplus }\left(\mathrm{aq}\right)$

3. $2\mathrm{Fe}\left(\mathrm{s}\right) + {\mathrm{O}}_2\left(\mathrm{g}\right) + 4\mathrm{H}{°}^{\oplus }\left(\mathrm{aq}\right) \to 2{\mathrm{Fe}}^{+2}\left(\mathrm{aq}\right) + 2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{aq}\right)$

4.  $\mathrm{Fe}\left(\mathrm{s}\right) \to {\mathrm{Fe}}^{+2}\left(\mathrm{aq}\right) + 2{\mathrm{e}}^{-}$

Which of the following is an incorrect statement :- 

1. Mercury cell is a primary cell providing a constant potential

2. During recharging lead storage cell works as electrolytic cell

3. Galvanised iron does not rust

4. In electrolytic cell reduction occurs at anode and in galvanic cell oxidation takes place at anode

For the cell reaction

${\mathrm{Cu}}_{{\mathrm{c}}_1}^{+2} \left(\mathrm{aq}\right) +\hspace{0.17em}\mathrm{Zn}\left(\mathrm{s}\right) \stackrel{ }{\to } {\mathrm{Zn}}_{{\mathrm{C}}_2}^{+2} \left(\mathrm{aq}\right) + \mathrm{Cu}\left(\mathrm{s}\right)$

the change in free energy at a given temperature is a function of 

(1) lnC₁

(2) ln$\frac{{\mathrm{C}}_2}{{\mathrm{C}}_1}$ 

(3) ln (C₁ +C₂)

(4) lnC₂

EMF of the following cell will be zero if

Pt(H₂)|H⁺||H⁺|(H₂)Pt

    P1   C1  C₂    P₂

(1) C₁P₁ = C₂P₂

(2) C₁P₂ = P₂C₁

(3) ${\mathrm{C}}_1^2{\mathrm{P}}_2 = {\mathrm{C}}_2^2{\mathrm{P}}_1$

(4) None of the above.

${\mathrm{E}}_{\raisebox{1ex}{${\mathrm{Ni}}^{+2}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{Ni}$}\right.}^0 = -0.25 \mathrm{V}, {\mathrm{E}}_{\raisebox{1ex}{${\mathrm{Au}}^{+3}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{Au}$}\right.}^0 = 1.50 \mathrm{V}$

the emf of Voltaic cell

$\mathrm{Ni} | {\mathrm{Ni}}^{+2}(1\mathrm{M}) || {\mathrm{Au}}^{+3}(1\mathrm{M}) \mathrm{Au} \mathrm{is}:-$

(1) 1.25 V

(2) -1.75 V

(3) 1.75 V

(4) 4 V