If  the standard emf of the reaction:

Fe + 2 Fe³⁺ →3Fe²⁺

will be:

• 0.330 V

• 1.653 V

• 1.212 V
• 1.212 V

A hypothetical electrochemical cell is shown below
A^- | A⁺ (xM)|| B⁺ (yM)|B⁺

The emf measured is +0.20 V. The cell reaction is:

• A⁺ + B  →  A + B⁺

• A⁺ + e^-  →  A ; B⁺ + e^-  → B^-

• the cell reaction cannot be predicted

• the cell reaction cannot be predicted

Concentration of the Ag+ ions in a saturated solution of Ag₂C₂O₄ is 2.2 ×10^–4 mol L^–1. Solubility product

• 2.42 × 10^–8

• 2.66 × 10^–12

• 4.5 × 10^–11

• 4.5 × 10^–11

In the electrochemical cell :
Zn|ZnSO₄(0.01M)||CuSO₄(1.0 M)|Cu, the emf of this Daniel cell is E₁. When the concentration of ZnSO₄ is changed to 1.0 M and that of CuSO₄ changed to 0.01 M, the emf changes to E₂. From the following, which one is the relationship between E₁ and E₂?
(Given, RT/F= 0.059)

• E₁= E₂

• E₁< E₂

• E₁> E₂

• E₁> E₂

When a lead storage battery is discharged;

• SO₂ is evolved

• lead sulphate is consumed

• lead is formed

• sulphuric acid is consumed

The value of reaction quotient [Q], for the following cell

Zn(s)|Zn²⁺ (0.01 M)|| Ag⁺ (1.25 M | Ag (s) is

• 156

• 125

• 1.25 x 10^-2

• 6.4 x 10^-3

The standard reduction potential for Zn²⁺/Zn, Ni²⁺/Ni and Fe²⁺/Fe are -0.76, -0.23 and -0.44 V, respectively.

The reaction X + Y²⁺ → X²⁺ + Y will be spontaneous when

• X = Ni, Y = Fe

• X = Ni, Y = Zn

• X =Fe, Y = Zn

• X = Zn, Y = Ni

For the cell reaction,

Pb + Sn²⁺ $\to$  Pb²⁺ + Sn

Given that, Pb $\to$ Pb²⁺, E$°$ = 0.13 V

Sn²⁺ +2e^- $\to$ Sn, E^$°$ = -0.14 V

What would be the ratio of cation concentration for which E = 0 ?

• $\frac{1}{4}$

• $\frac{1}{2}$

• $\frac{1}{3}$

• $\frac{1}{1}$

619.

In the reaction, 

X + I₂ + 2HCl $\to$SnCl₄ + 2HI

The correct option regarding X is/ are

• It is an strong reducing agent

• It is an angular molecule

• It is used as a reagent in test of Hg²⁺ radical

• All of the above

The E^$°$ values for Mn and Zn are more negative than expected because

• they have either half-filled and fully-filled configurations

• they can easily donate electrons

• it is quite easy to remove electrons from their orbitals

• None of the above