Calculate the mass of Ag deposited at cathode when a current of 2 amperes was passed through a solution of AgNO3 for 15 minutes.
(Given : Molar mass of Ag = 108 g mol–1 1F = 96500 C mol–1)
Which among the following metals is employed to provide cathodic protection to iron?
Zinc
Nickel
Tin
Lead
Two Faraday of electricity is passed through a solution of CuSO4. The mass of copper deposited at the cathode is: (at. mass of Cu = 63.5 amu)
0 g
63.5 g
2 g
2 g
The equivalent conductance of NaCl at concentration C at infinite dilution are λC and λ∞ respectively. The correct relationship between λC and λ∞ is given as (where the constant B is positive)
λC = λ∞ +(B)C
λC = λ∞ -(B)C
λC = λ∞ -(B)
λC = λ∞ -(B)
Given below are the half-cell reactions
Mn2+ + 2e- → Mn; Eo = - 1.18 eV
2(Mn3+ + e- →Mn2+); Eo = +1.51 eV
The Eo for 3Mn2+ → Mn + 2Mn3+ will be
-2.69 V; the reaction will not occur
-2.69 V; the reaction will occure
-0.33 V; the reaction will not occur
-0.33 V; the reaction will not occur
A.
-2.69 V; the reaction will not occur
Standard element potential of reaction [ Eo] can be calculated as
Eocell = ER-EP
where ER = SRP of reactant
EP = SRP of product
If Eocell = +ve, then the reaction is spontaneous otherwise non-spontaneous.
therefore, For Mn2+ disproportionation
Eo = - 1.51 V - 1.18 V = - 2.69 V < 0
Given,
Based on the data given above, strongest oxidising agent will be
Cl
Cr3+
Mn2+
Mn2+