When 0.1 mole of MnO^2-₄ is oxidised, the quantity of electricity required to completely oxidise MnO^2-₄ to MnO^-₄ is 

The Zn acts as sacrificial or cathodic protection to prevent rusting of iron because:

The standard reduction potential for Fe²⁺|Fe and Sn²⁺|Sn ,electrodes are -0.44 V and -0.14 V respectively. For the cell reaction, Fe²⁺ + Sn $\stackrel{ }{\to }$ Fe + Sn²⁺, the standard Emf is:

On electrolysing a solution of dilute H₂SO₄ between platinum electrodes, the gas evolved at the anode and cathode are respectively:

What mass of copper will be deposited by passing 2 faraday of electricity through a solution of Cu(II) salt?

In electrolysis of NaCl when Pt electrode is taken then H₂ is liberated at cathode while with Hg cathode it forms sodium amalgam because :

The same amount of electricity was passed through two cells containing molten Al₂O₃ and molten NaCl. If 1.8g of Al were liberated in one cell, the amount of Na liberated in the other cell is:

If mercury is used as cathode in the electrolysis of aqueous NaCl solution, the ions discharged at cathode are:

A gas X at 1 atm is bubbled through a solution containing a mixture of 1MY^- and 1MZ^- at 25$°$C. If the reduction potential of Z > Y > X, then:

The solution of CuSO₄ in which copper rod is immersed is diluted to 10 times, the reduction electrode potential:

A solution containing one mole per litre each of Cu(NO₃)₂, AgNO₃, Hg₂(NO₃)₂ and Mg(NO₃)₂ is being electrolysed by using inert electrodes. The values of standard electrode potentials in volt (reduction potentials) are,

Ag⁺ /Ag= 0.80, ${\mathrm{Hg}}_2^{2+}$/2Hg = 0.79,

Cu²⁺/Cu = +0.34 and Mg²⁺/Mg =-2.37

With increasing voltage, the sequency of deposition of metals on the cathode wil be:

The highest electrical conductivity of the following aqueous solution is of:

How many columbs of electricity are consumed when 100 mA current is passed through a solution of AgNO₃ for 30 minute during an electrolysis experiment?

Standard reduction potentials at 25$°$C of Li⁺/Li, Ba²⁺/Ba, Na⁺/Na and Mg²⁺/Mg are -3.05, -2.90, -2.71 and -2.37 V respectively. Which one of the following is the strongest oxidising agent ?

Equivalent conductances of NaCl, HCl and C₂H₅COONa at infinite dilution are 126.45, 426.16 and 91${\mathrm{\Omega }}^{-1}{\mathrm{cm}}^2$. The equivalent conductance of C₂H₅COOH is : 

When an electric current is passed through acidulated water, 112 mL of hydrogen gas at STP collects at the cathode in 965 second. The current passed, in ampere is:

The electric charge for electrode deposition of 1g equivalent of a substance is:

The change in reduction potential of a hydrogen electrode change when its solution initialy at pH=0 is neutralised to pH =7 , is -

 The cell reaction for the given cell is spontaneous if:

Pt_cl2|cl^-(1M)||Cl^-(1M)|Pt_Cl2

Each of the three metals X, Y and Z were put in turn into aqueous solution of the other two.

X + Salt of Y (or Z) ⟶  Y (or Z) + Salt of X.

Which observation is probably incorrect?

Cu⁺(aq) is unstable in solution and undergoes simultaneous oxidation and reduction according to the reaction 

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

Choose the correct E0 for above reaction if E⁰_cu²⁺/cu = 0.34 V and E⁰_cu²⁺/cu+ = 0.15 V 

On the basis of the information available from the reaction.

$\frac{4}{3}\mathrm{Al} + {\mathrm{O}}_2 \stackrel{ }{\to }\frac{2}{3}{\mathrm{Al}}_2{\mathrm{O}}_3, ∆G =-827\mathrm{kJ} {\mathrm{mol}}^{-1}$ 

of O₂, the minimum EMF required to carry out the electrolysis of Al₂O₃ is : (F=96500 C mol^-1) 

4.5 g of aluminium (atomic mass 27u) is deposited at cathode from Al³⁺ solution by a certain quantity of electric charge. The volume of hydrogen produced at STP from H⁺ ions in solution by the same quantity of electric charge will be

A certain current liberates 0.504 g of hydrogen in 2 hr. How many gram of copper can be liberated by the same current flowing for the same time in CuSO₄ solution?

For the reductidon of silver ions with copper metal, the standard  cell potential was found to be + 0.46 V at 25⁰C. The value of standard Gibbs energy, -$\Delta$G⁰ will be (F = 96500 Cmol^-1)

A solution of sodium sulphate in water is electrolysed using inert electrodes. The products at the cathode and anode are respectively:

If a salt bridge is removed from the two half cells, the voltage:

Two electrolytic cells, one containing acidified ferrous chloride and another acidified ferric chloride are connected in series. The ratio of iron deposited at cathodes in the two cells when electricity is passed through the cells will be:

If the half-cell reaction A+e$\to$A^- has a large negative reduction potential, it follows that:

Pick out the incorrect statement