571.

If an element A is placed in an electrochemical series above element B but below element C, then the order of oxidation power of elements is

• C>A>B

• B>A>C

• A>B>C

• C>B>A

Given, ${\mathrm{E}}_{{\mathrm{Cr}}^{3+}/ \mathrm{Cr}}^{°} = -0.72 \mathrm{V}, {\mathrm{E}}_{{\mathrm{Fe}}^{2+}/ \mathrm{Fe}}^{°} = -0.42 \mathrm{V}.$The potential for the cell Cr | Cr³⁺ (0.1 M) || Fe²⁺ (0.01 M) | Fe is

• 0.26 V

• 0.399 V

• -0.399 V

• -0.26 V

A lead storage battery is discharged. During the charging of this battery, the reaction that occurs at anode, is

• ${\mathrm{PbSO}}_4 \left(\mathrm{s}\right) + 2{\mathrm{e}}^{-} \to \mathrm{Pb}\left(\mathrm{s}\right) +\hspace{0.17em}{\mathrm{SO}}_4^{2-}\left(\mathrm{aq}\right)$

• ${\mathrm{PbSO}}_4 \left(\mathrm{s}\right) + 2{\mathrm{H}}_2\mathrm{O} \to {\mathrm{PbO}}_2\left(\mathrm{s}\right) +\hspace{0.17em}{\mathrm{SO}}_4^{2-}\left(\mathrm{aq}\right)+ 4{\mathrm{H}}^{+}\left(\mathrm{aq}\right) + 2{\mathrm{e}}^{-}$

• ${\mathrm{PbSO}}_4 \left(\mathrm{s}\right) \to {\mathrm{Pb}}^{2+}\left(\mathrm{aq}\right) +\hspace{0.17em}{\mathrm{SO}}_4^{2-}\left(\mathrm{aq}\right)$

• ${\mathrm{PbSO}}_4 \left(\mathrm{s}\right) +2{\mathrm{H}}_2\mathrm{O} + 2{\mathrm{e}}^{-} \to {\mathrm{PbO}}_2\left(\mathrm{s}\right) +\hspace{0.17em}{\mathrm{SO}}_4^{2-}\left(\mathrm{aq}\right)+ 2{\mathrm{H}}^{+}\left(\mathrm{aq}\right)$

Which one of the following is correct plot of Λ_m ( in S cm² mol^-1) and √C (in mol/L^1/2) for KCl solution? ( y= Λ_m; x= √C)

Considerthe following electrode processes of a cell,

${\mathrm{Cl}}^{-} \to \frac{1}{2}{\mathrm{Cl}}_2 + {\mathrm{e}}^{-} [\mathrm{MCl} + {\mathrm{e}}^{-} \to \mathrm{M} + {\mathrm{Cl}}^{-}]$

If EMF of this cell is-1.140 V and E° value of the cell is -0.55 V at 298 K, the value of the equilibrium constant of the sparingly soluble salt MCl is in the order of

• 10^-10

• 10^-8

• 10^-7

• 10^-11

Consider the single electrode process 4H⁺ + 4e^- $\rightleftharpoons$ 2H₂ catalysed by platinum black electrode in HCl electrolyte. The potential of the electrode is -0.059 V. SHE. What is the concentration of the acid in the hydrogen half cell if the H₂ pressure is 1 bar?

4H⁺ + 4e^- $\rightleftharpoons$ 2H₂ 

• 1 M

• 10 M

• 0.1 M

• 0.01 M

Given that,

 $$\begin{gathered} {\mathrm{E}}_{{\mathrm{O}}_2/ {\mathrm{H}}_2\mathrm{O}}^{⊝} = +1.23 \mathrm{V} \\ {\mathrm{E}}_{{\mathrm{S}}_2{\mathrm{O}}_8^{2-}/ {\mathrm{SO}}_4^{2-}}^{⊝} = 2.05 \mathrm{V} \\ {\mathrm{E}}_{{\mathrm{Br}}_2/ \mathrm{Br}}^{⊝} = +1.09 \mathrm{V} \\ {\mathrm{E}}_{{\mathrm{Au}}^{3+}/ \mathrm{Au}}^{⊝} = +1.4 \mathrm{V} \end{gathered}$$

The strongest oxidising agent is

• Br²⁺

• O₂

• Au³⁺

• S₂O${}_8^{2-}$

A solution of Ni(NO₃)₂ is electrolysed between platinum electrodes using 0.1 Faraday electricity. How many mole of Ni will be deposited at the cathode?

• 0.10

• 0.15

• 0.20

• 0.05

Calculate the standard cell potential (in V) of the cell in which following reaction takes place :

Fe²⁺ (aq) + Ag⁺(aq) → Fe³⁺(aq) + Ag(s)

Given that 

E°_{Ag⁺/ Ag} = xV

E°_{Fe²⁺/ Fe} = yV

E°_{Fe³⁺/ Fe} = zV

• x -y

• x-z

• x +2y-3z

• x+y-z

Consider the statement S1 snd S2:
S1: Conductivity always increases with decreases in the concentraction of electrolyte
S2: Molar Conductivity always increase with decreases in the concentration of Electrolyte.

The correct option among the following

• S1 is correct and S2 is wrong

• both S1 and S2 are correct

• Both S1 and S2 are wrong

• S1 is wrong S2 is correct