The metal that cannot be produced on reduction of its oxide by aluminium is :

(1) K                                                        

(2) Mn

(3) Cr                                                      

(4) Fe

The calomel electrode is reversible with respect to-

1. Mercury                                       

2. $H^{+}$

3. $H{g}^{2+}$                                          

4. $C{l}^{-}$

The standard oxidation potentials are:

Cu → Cu²⁺ + 2e⁻ ; E°ₒₓ = −0.34 V
Cu⁺ → Cu²⁺ + e⁻ ; E°ₒₓ = −0.16 V

Calculate the standard electrode potential for:

Cu⁺ + e⁻ → Cu

1. 0.18V  

2. 0.52V

3. 0.82V    

4. 0.49V

 ${\mathrm{E}}^0<mspace\; width="1em"></mspace>\mathrm{for}<mspace\; width="1em"></mspace>\mathrm{the}<mspace\; width="1em"></mspace>\mathrm{reaction}<mspace\; width="1em"></mspace>$
$\mathrm{Fe}<mspace\; width="1em"></mspace>+<mspace\; width="1em"></mspace>{\mathrm{Zn}}^{2+}<mspace\; width="1em"></mspace>=<mspace\; width="1em"></mspace>\mathrm{Zn}<mspace\; width="1em"></mspace>+<mspace\; width="1em"></mspace>{\mathrm{Fe}}^{2+}<mspace\; width="1em"></mspace>\mathrm{is}<mspace\; width="1em"></mspace>–<mspace\; width="1em"></mspace>0.35<mspace\; width="1em"></mspace>\mathrm{V}.$
The   given   cell   reaction   is: 

1. Feasible  

2. Not feasible

3. In equilibrium 

4. None of the above

The  number of electrons involved in the deposition of 63.5 g of Cu from a solution of $CuS{O}_4$ is:

1 $6.022$ $\times$ ${10}^{23}$ $$

2 $3.011$ $\times$ ${10}^{23}$ $$

3 $12.044$ $\times$ ${10}^{23}$ $$

4 $$ $6.022$ $\times$ ${10}^{22}$

 The reduction potential of a half-cell consisting of a Pt electrode immersed in \(1.5 \text{M}~ F e^{2+} \text { and } 0.015 \text{M}~ F e^{3+}\) solution at 25 ^oC is:
\((E_{F e^{+3}, F e^{+2}}^{\circ}=+0.770 ~V )\)
1.   0.652 V                                                   
2.   0.88 V
3.   0.710 V                                                   
4.   0.850 V

The volume of gases liberated at STP when a charge of 2F is passed
through aqueous solution of sodium phosphate, is :

1. 11.2L                                           

2. 44.8L

3. 33.6L                                           

4. 22.4L

The $E°$ in the given diagram is,
(1) 0.5                                     

(2) 0.6

(3) 0.7                                    

(4) 0.8

The temperature coefficient of a standard Cd-cell is $–5.0<mspace\; width="1em"></mspace>\times <mspace\; width="1em"></mspace>{10}^{-5}<mspace\; width="1em"></mspace>V{k}^{-1}$ whose emf at $25°C$ is 1.018 V. During the cell operation, the temperature will -

(1) increase                                      

(2) decreases

(3) either                                         

(4) remains constant

Na-amalgam is prepared by electrolysis of NaCl solution using liquid Hg as a cathode. How long should the current of 10 amp. is passed to produce 10% Na – Hg on a cathode of 10 gm Hg. (atomic mass of Na = 23).

1.   7.77 min.                                               
2.   9.44 min.
3.   5.24 min.                                               
4.   11.39 min.