Electrochemistry

The equation that is incorrect is :

Potassium chlorate is prepared by the
electrolysis of KCl in basic solution
6OH- + Cl- \(\to\) ClO3- + 3H2O + 6e-
If only 60% of the current is utilized in the
reaction, the time (rounded to the nearest hour)
required to produce 10 g of K...

For the given cell :
Cu(s) | Cu2+(C1M) || Cu2+(C2M) | Cu(s)
change in Gibbs energy (\(\Delta\)G) is negative, if :

An oxidation-reduction reaction in which 3 electrons are transferred has a \(\Delta\)Gº of 17.37 kJ mol–1 at
25 oC. The value of Eo
cell (in V) is ______ × 10–2.
(1 F = 96,500 C mol–1)

The variation of molar conductivity with concentration of an electrolyte (X) in aqueous solution
is shown in the given figure.

The electrolyte X is :

\(E_{C{u^{2 + }}|Cu}^0\) = +0.34 V
\(E_{Z{n^{2 + }}|Zn}^0\) = -0.76 V
Identify the incorrect statement from the option
below for the above cell :

250 mL of a waste solution obtained from the
workshop of a goldsmith contains 0.1 M AgNO3
and 0.1 M AuCl. The solution was electrolyzed
at 2V by passing a current of 1A for 15
minutes. The metal/metals electrodeposited will
be
[ $$E_{A{g^ +...

The photoelectric current from Na (Work function, w0
= 2.3 eV) is stopped by the output voltage of
the cell Pt(s) | H2
(g, 1 Bar) | HCl (aq., pH =1) | AgCl(s) | Ag(s).
The pH of aq. HCl required to stop the photoelectric current form K(w0
...

Let CNaCl
and CBaSO4 be the conductances (in S) measured for saturated aqueous solutions of NaCl
and BaSO4, respectively, at a temperature T.
Which of the following is false?

An acidic solution of dichromate is electrolyzed
for 8 minutes using 2A current. As per the
following equation
Cr2O72-
+ 14H+ + 6e– \(\to\) 2Cr3+ + 7H2O
The amount of Cr3+ obtained was 0.104 g. The
efficiency of the process(in%) is
(Take...

The Gibbs change (in J) for the given reaction at
[Cu2+] = [Sn2+] = 1 M and 298K is :
Cu(s) + Sn2+(aq.) \(\to\) Cu2+(aq.) + Sn(s);
(\(E_{S{n^{2 + }}|Sn}^0 = - 0.16\,V\),
\(E_{C{u^{2 + }}|Cu}^0 = 0.34\,V\))
Take F = 96500 C mol–1)

For the disproportionation reaction
2Cu+(aq) ⇌ Cu(s) + Cu2+(aq) at 298 K. ln K
(where K is the equilibrium constant) is
___________ × 10–1.
Given :
(\(E_{C{u^{2 + }}/C{u^ + }}^0 = 0.16V\)
\(E_{C{u^ + }/Cu}^0 = 0.52V\)
$${{RT} \over F} = 0.0...

The anodic half-cell of lead-acid battery is recharged using electricity of 0.05 Faraday. The amount of PbSO4 electrolyzed in g during the process is : (Molar mass of PbSO4 = 303 g mol\(-\)1)

If the standard electrode potential for a cell is 2 V at 300 K, the equilibrium constant (K) for the reaction
Zn(s) + Cu2+ (aq) \(\rightleftharpoons\) Zn2+(aq) + Cu(s)
at 300 K is approximately,
(R = 8 JK\(-\)1mol\(-\)1, F = 96000 C mol$...

The standard Gibbs energy for the given cell
reaction in kJ mol–1 at 298 K is :
Zn(s) + Cu2+ (aq) \(\to\) Zn2+ (aq) + Cu (s),
E° = 2 V at 298 K
(Faraday's constant, F = 96000 C mol–1)

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?

Given that \({E^\Theta }_{{O_2}/{H_2}O} = 1.23\,V\) ;
\({E^\Theta }_{{S_2}O_8^{2 - }/SO_4^{2 - }} = 2.05\,V\)
\({E^\Theta }_{B{r_2}/B{r^ - }} = 1.09\,V\)
\({E^\Theta }_{A{u^{3 + }}/Au} = 1.4\,V\)
The strongest oxidizing agent is :

Calculate the standard cell potential in (V) of the
cell in which following reaction takes place :
Fe2+(aq) + Ag+(aq) \(\to\) Fe3+(aq) + Ag (s)
Given that
\(E_{A{g^ + }/Ag}^o = xV\)
\(E_{Fe^{2+ }/Fe}^o = yV\)
\(E_{Fe^{3+ }/Fe}^o = zV\)

The standard electrode potential \({E^o }\) and its temperature coefficient \(\left( {{{d{E^o }} \over {dT}}} \right)\) for a cell are 2V and \(-\) 5 \(\times\) 10\(-\)4 VK\(-\)1 at 300 K respectively.
The cell reaction is
Zn(s) + Cu2+ ...

\(\wedge _m^ \circ\) for NaCl, HCl and NaA are 126.4, 425.9 and 100.5 S cm2 mol–1, respectively. If the conductivity of 0.001 M HA is-
5 \(\times\) 10–5 S cm–1, degree of dissociation of HA is -

Given
CO3+ + e– \(\to\) CO2+ ; Eo = + 1.81 V
Pb4+
+ 2e– \(\to\) Pb2+ ; Eo = + 1.67 V
Ce4+
+ e– \(\to\) Ce3+
; Eo = + 1.61 V
Bi3+ + 3e– \(\to\) Bi ; Eo = + 0.20 V
Oxidizing power of the species will increase in the order :

For the cell Zn(s) |Zn2+ (aq)| |Mx+ (aq)| M(s), different half cells and their standard electrode potentials are given below :

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Given the equilibrium constant:
KC of the reaction :
Cu(s) + 2Ag+ (aq) \(\to\) Cu2+ (aq) + 2Ag(s) is 10 \(\times\) 1015, calculate the E\(_{cell}^0\) of this reaciton at 298 K [2.303 \({{RT} \over F}\) at 298 K = 0.059V]

Consider the following reduction processes :
Zn2+ + 2e– \(\to\) Zn(s) ; Eo = – 0.76 V
Ca2+ + 2e– \(\to\) Ca(s); Eo = –2.87 V
Mg2+ + 2e– \(\to\) Mg(s) ; Eo = – 2.36 V
Ni2 + 2e– \(\to\) Ni(s) ; Eo = – 0.25
The reducing power of the m...

In the cell
Pt\(\left| {\left( s \right)} \right|\)H2(g, 1 bar)\(\left| {HCl\left( {aq} \right)} \right|\)AgCl\(\left| {\left( s \right)} \right|\)Ag(s)|Pt(s)
the cell potential is 0.92 V when a 10–6 molal HCl solution is used. The stand...

Consider the statements S1 and S2
S1 : Conductivity always increases with decrease in the concentration of electrolyte.
S2 : Molar conductivity always increases with decrease in the concentration of electrolyte.
The correct option among the...

Which one of the following graphs between molar conductivity (\({\Lambda _m}\)) versus \(\sqrt C\) is correct ?

When 9.65 ampere current was passed for 1.0 hour into nitrobenzene in acidic medium, the amount of p-aminophenol produced is :

When an electric currents passed through acidified water, 112 mL of hydrogen gas at N.T.P. was collected at the cathode in 965 seconds. The current passed, in ampere, is :

How long (approximate) should water be electrolysed by passing through 100 amperes current so that the
oxygen released can completely burn 27.66 g of diborane?
(Atomic weight of B = 10.8 u)

To find the standard potential of M3+/M electrode,the following cell is constituted : Pt/M/M3+(0.001 mol L−1 )/Ag+(0.01 mol L−1 )/Ag
The emf of the cell is found to be 0.421 volt at 298 K. The standard potential of half reaction M3+ + 3e−...

Consider the following standard electrode potentials (Eo in volts) in aqueous solution :

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What is the standard reduction potential (Eo) for Fe3+ \(\to\) Fe ?
Given that :
Fe2+ + 2e\(-\) \(\to\) Fe; \(E_{F{e^{2 + }}/Fe}^o\) = \(-\)0.47 V
Fe3+ + e\(-\) \(\to\) Fe2+; \(E_{F{e^{3 + }}/F{e^{2 + }}}^o\) = +0.77 V

Given
\(E_{C{l_2}/C{l^ - }}^o\) = 1.36 V, \(E_{C{r^{3 + }}/Cr}^o\) = - 0.74 V
\(E_{C{r_2}{O_7}^{2 - }/C{r^{3 + }}}^o\) = 1.33 V, \(E_{Mn{O_4}^ - /Mn ^{2+}}^o\) = 1.51 V
Among the following, the strongest reducing agent is :

What will occur if a block of copper metal is dropped into a beaker containing a
solution of 1M ZnSO4?

Oxidation of succinate ion produces ethylene and carbon dioxide gases. On passing 0.2 Faraday electricity through an aqueous solution of potassium succinate, the total volume of gases (at both cathode and anode) at STP (1 atm and 273 K) is ...

Identify the correct statement :

Galvanization is applying a coating of :

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)

Resistance of 0.2 M solution of an electrolyte is 50 \(\Omega\). The specific conductance of the solution is 1.4 S m-1. The resistance of 0.5 M solution of the same electrolyte is 280 \(\Omega\). The molar conductivity of 0.5 M solution of ...

The equivalent conductance of NaCl at concentration C and at infinite dilution are \({\lambda _C}\) and \({\lambda _\infty }\), respectively. The correct relationship between \({\lambda _C}\) and \({\lambda _\infty }\) is given as:
(where...

Given below are the half-cell reactions:
Mn2+ + 2e- \(\to\) Mn; Eo = -1.18 V
2(Mn3+ + e- \(\to\) Mn2+); Eo = +1.51 V
The Eo for 3Mn2+ \(\to\) Mn + 2Mn3+ will be :

Given
\(E_{C{r^{2 + }}/Cr}^o\) = -0.74 V; \(E_{MnO_4^ - /M{n^{2 + }}}^o\) = 1.51 V
\(E_{C{r_2}O_7^{2 - }/C{r^{3 + }}}^o\) = 1.33 V; \(E_{Cl/C{l^ - }}^o\) = 1.36 V
Based on the data given above, strongest oxidising agent will be :

The standard reduction potentials for Zn2+/ Zn, Ni2+/ Ni, and Fe2+/ Fe are –0.76, –0.23 and –0.44 V respectively. The reaction X + Y2+ \(\to\) X2+ + Y will be spontaneous when :

The reduction potential of hydrogen half cell will be negative if :

The Gibbs energy for the decomposition of Al2O3 at 500oC is as follows :
\({2 \over 3}A{l_2}{O_3}\) \(\to\) \({4 \over 3}Al + {O_2}\), \({\Delta _r}G\) = + 966 kJ mol–1
The potential difference needed for electrolytic reduction of Al2O3 at ...

The correct order of \(E_{{M^{2 + }}/M}^o\) values with negative sign for the four successive elements Cr, Mn, Fe
and Co is :

Given : \(E_{F{e^{3 + }}/Fe}^o\) = -0.036V; \(E_{F{e^{2 + }}/Fe}^o\) = -0.439 V
The value of standard electrode potential for the change,
Fe3+ (aq) + e- \(\to\) Fe2+ (aq) will be

In a fuel cell methanol is used as fuel and oxygen gas is used as an oxidizer. The reaction is
CH3OH(l) + 3/2O2 \(\to\) CO2 (g) + 2H2O (l)
At 298K standard Gibb’s energies of formation for CH3OH(l), H2O(l) and CO2 (g) are -166.2, -237.2 a...

Given \(E_{C{r^{3 + }}/Cr}^o\) = -0.72 V; \(E_{Fe^{2+}/Fe}^o\) = -0.42V, The potential for the cell Cr | Cr3+ (0.1M) || Fe2+ (0.01 M) | Fe is