Electrochemistry ,PYQsNEET,[Difficult level:Easy] 15 Questions

 

15Qs

 Question:  From NCERT  | NEET 2021   || [Difficult level:Easy] ||| 

.The molar conductance of NaCl, HCI, and CH3COONa at infinite dilution are 126.45, 426.16, and 91.0 S cm mol-1 respectively. The molar conductance of CH3COOH at infinite dilution is. Choose the right option for your answer.

1. 698.28 S cm2 mol-1

2. 540.48 S cm2 mol-1

3. 201.28 S cm2 mol-1

4. 390.71 S cm2 mol-1

.

.Subtopic:   Kohlrausch Law & Cell Constant |

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 Answer ▽ ✅Verified 

4. 390.71 S cm2 mol-1

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 Question:  From NCERT  | NEET 2020   || [Difficult level:Easy] ||| 

.In a typical fuel cell, the reactants (R) and product (P) are :-

(1) $R=H_{2\left(g\right)},O_{2\left(g\right)};P=H_2{O}_{2\left(l\right)}$

(2) $R=H_{2\left(g\right)},O_{2\left(g\right)};P=H_2{O}_{\left(l\right)}$

(3) $R=H_{2\left(g\right)},O_{2\left(g\right)},C{l}_2\left(g\right);P=HCl{O}_{4\left(aq\right)}$

(4) $R=H_{2\left(g\right)},N_{2\left(g\right)};P=N{H}_{3\left(aq\right)}$

.

.Subtopic:  Batteries & Salt Bridge

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 Answer ▽ ✅Verified 

(2) $R=H_{2\left(g\right)},O_{2\left(g\right)};P=H_2{O}_{\left(l\right)}$

fuel cell

Production of electricity by thermal plants is not a very efficient method
and is a major source of pollution. In such plants, the chemical energy
(heat of combustion) of fossil fuels (coal, gas or oil) is first used for
converting water into high pressure steam. This is then used to run
a turbine to produce electricity. We know that a galvanic cell directly
converts chemical energy into electricity and is highly efficient. It is
now possible to make such cells in which reactants are fed continuously
to the electrodes and products are removed continuously from the
electrolyte compartment. Galvanic cells that are designed to convert
the energy of combustion of fuels like hydrogen, methane, methanol,
etc. directly into electrical energy are called fuel cells.

to thermal plants whose efficiency is about 40%. There has been

tremendous progress in the development of new electrode materials,

better catalysts and electrolytes for increasing the efficiency of fuel cells.

These have been used in automobiles on an experimental basis. Fuel

cells are pollution free and in view of their future importance, a variety

of fuel cells have been fabricated and tried.

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 Question:  From NCERT  | NEET 2016   || [Difficult level:Easy] ||| 

.The molar conductivity of a 0.5 mol/dm3 solution of AgNO3 with electrolytic conductivity of 5.76x10-3 S cm-1 at 298 K is

(1) 2.88 S cm2/mol

(2) 11.52 S cm2/mol

(3) 0.086 S cm2/mol

(4) 28.8 S cm2/mol

.Subtopic:  Conductance & Conductivity |

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 Answer ▽ ✅Verified 

(2) 11.52 S cm2/mol

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 Question:  From NCERT  | NEET 2016   || [Difficult level:Easy] ||| 

.The number of electrons delivered at the cathode during electrolysis by a current of 1 ampere in 60 seconds is (charge on electron = 1.60 x 10-19 C)

1. 6 x 1023

2. 6 x 1020

3. 3.75 x 1020

4. 7.48 x 1023

.

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 Answer ▽ ✅Verified 

3. 3.75 x 1020

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 Question:  From NCERT  | NEET 2015   || [Difficult level:Easy] ||| 

.A device that converts energy of combustion of fuels like hydrogen and methane, directly

into electrical energy is known as

1. fuel cell

2. electrolytic cell

3. dynamo

4. Ni-Cd cell

.

.Subtopic:  Electrolytic & Electro-Chemical Cell 

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 Answer ▽ ✅Verified 

1. fuel cell

Production of electricity by thermal plants is not a very efficient method
and is a major source of pollution. In such plants, the chemical energy
(heat of combustion) of fossil fuels (coal, gas or oil) is first used for
converting water into high pressure steam. This is then used to run
a turbine to produce electricity. We know that a galvanic cell directly
converts chemical energy into electricity and is highly efficient. It is
now possible to make such cells in which reactants are fed continuously
to the electrodes and products are removed continuously from the
electrolyte compartment. Galvanic cells that are designed to convert
the energy of combustion of fuels like hydrogen, methane, methanol,
etc. directly into electrical energy are called fuel cells.

to thermal plants whose efficiency is about 40%. There has been

tremendous progress in the development of new electrode materials,

better catalysts and electrolytes for increasing the efficiency of fuel cells.

These have been used in automobiles on an experimental basis. Fuel

cells are pollution free and in view of their future importance, a variety

of fuel cells have been fabricated and tried.

 ⬆️Prev____@organised notes_____Next⬇️

 Question:  From NCERT  | NEET 2013   || [Difficult level:Easy] ||| 

.A button cell used in watches functions as following

Zn(s) + Ag2O(s) + H2O (l) $\rightleftharpoons$2Ag(s) + Zn2+(aq) + 2OH-(aq)

If half cell potentials are

${{\mathrm{Zn}}^{2+}}_{\left(\mathrm{aq}\right)}+2e^{-}\to {\mathrm{Zn}}_{\left(x\right)};E^o=-0.76V{\mathrm{Ag}}_2{O}_{\left(s\right)}+H_2{O}_{\left(l\right)}+2e^{-}\to 2{\mathrm{Ag}}_{\left(s\right)}+2{{\mathrm{OH}}^{-}}_{\left(\mathrm{aq}\right)};E^o=0.34V$

The cell potential will be

1. 0.84 V

2. 1.34 V

3. 1.10 V

4. 0.42 V

.Subtopic:  Electrolytic & Electro-Chemical Cell

.

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 Answer ▽ ✅Verified 

3. 1.10 V

In the button cells widely used in watches and other devices the following

reaction takes place:

Zn(s) + Ag2O(s) + H2O(l ) ®→Zn2+(aq) + 2Ag(s) + 2OH–(aq)

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 Question:  From NCERT  | NEET 2013   || [Difficult level:Easy] ||| 

.A hydrogen gas electrode is made by dipping platinum wire in a solution of HCl of pH = 10 and by passing hydrogen gas around the platinum wire at one atm pressure. The oxidation potential of electrode would be : 

 

1. 0.59 V

2. 0.118 V

3. 1.18 V

4. 0.059 V

.

.Subtopic:  Relation between Emf ,G, Kc & pH |

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 Answer ▽ ✅Verified 

1. 0.59 V

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 Question:  From NCERT  | NEET 2011   || [Difficult level:Easy] ||| 

.Standard electrode potential of three metals X, Y and Z are -1.2 V, +0.5 V and -3.0 V respectively. The reducing power of these metals will be : 

1.  Y > X > Z

2.  Z > X > Y

3.  X > Y > Z

4.  Y > Z > X

.

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 Answer ▽ ✅Verified 

2.  Z > X > Y

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 Question:  From NCERT  | NEET 2011   || [Difficult level:Easy] ||| 

.Standard electrode potential for Sn4+/Sn2+ couple is +0.15 V and that for the Cr3+/Cr couple is -0.74. These two couple in their standard state are connected to make a cell. The cell potential will be : 

1.  +0.89 V

2.  +0.18 V

3.  +1.83 V

4.  +1.199 V

.

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 Answer ▽ ✅Verified 

1.  +0.89 V

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 Question:  From NCERT  | NEET 2009   || [Difficult level:Easy] ||| 

.Given, 

(i) ${\mathrm{Cu}}^{2+}+2e^{-}\to \mathrm{Cu}$    Eo = 0.337 V 
(ii) ${\mathrm{Cu}}^{2+}+e^{-}\to {\mathrm{Cu}}^{+}$  Eo = 0.153 V 
Electrode potential, E0 for the reaction, 
${\mathrm{Cu}}^{+}+e^{-}\to \mathrm{Cu}$, will be : 

1. 0.52 V

2. 0.90 V

3. 0.30 V

4. 0.38 V

.

.

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 Answer ▽ ✅Verified 

1. 0.52 V

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 Question:  From NCERT  | NEET 2007   || [Difficult level:Easy] ||| 

.A steady current of 1.5 A flows through a copper voltmeter for 10 min. If the electrochemical equivalent of copper is 30 × 10-5 gC-1, the mass of copper deposited on the electrode will be :

1. 0.40 g

2. 0.50 g

3. 0.67 g

4. 0.27 g

.

.

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 Answer ▽ ✅Verified 

4. 0.27 g

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 Question:  From NCERT  | NEET 2008   || [Difficult level:Easy] ||| 

.The sequence of ionic mobility in aqueous solution is : 

1.  K+> Na+> Rb+> Cs+

2.  Cs+> Rb+> K+> Na+

3.  Rb+> K+> Cs+> Na+

4.  Na+> K+> Rb+> Cs+

.

.

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 Answer ▽ ✅Verified 

2.  Cs+> Rb+> K+> Na+

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