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प्रश्न
What is electrode potential?
What do you understand by electrode potential?
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उत्तर
The tendency of an electrode to lose or gain electrons when it is in contact with its own ions in solution is called electrode potential. The electrode potentials are responsible for the e.m.f. of a galvanic cell.
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संबंधित प्रश्न
Can you store copper sulphate solutions in a zinc pot?
Arrange the following metals in the order in which they displace each other from the solution of their salts.
\[\ce{Al, Cu, Fe, Mg}\] and \[\ce{Zn}\]
Construct a labelled diagram for the following cell:
`Zn|Zn^(2+)(1M)||H^+(1M)|H_(2(g,1atm))|Pt`
How many electrons flow through a metllic wire if a current of 0·5 A is passed for 2 hours? (Given : 1 F = 96,500 C mol−1)
For the electrochemical cell:
\[\ce{M | M+ || X- | X}\];
\[\ce{E^{\circ}_{{M^{+}/{M}}}}\] = 0.44 V,
\[\ce{E^{\circ}_{X/X^-}}\] = 0.33 V
Which of the following is TRUE for this data?
A solution of Cu(NO3)2 is electrolyzed between platinum electrodes using 0.1 Faraday electricity. How many moles of Cu will be deposited at the cathode?
At 25°C, the emf of the following electrochemical cell.
\[\ce{Ag_{(s)} | Ag^+ (0.01 M) | | Zn^{2+} {(0.1 M)} | Zn_{(s)}}\] will be:
(Given \[\ce{E^0_{cell}}\] = −1.562 V)
Describe the electrolysis of molten NaCl using inert electrodes.
Write a note on sacrificial protection.
A galvanic cell has electrical potential of 1.1V. If an opposing potential of 1.1V is applied to this cell, what will happen to the cell reaction and current flowing through the cell?
Match the terms given in Column I with the items given in Column II.
| Column I | Column II |
| (i) Λm | (a) intensive property |
| (ii) ECell | (b) depends on number of ions/volume |
| (iii) K | (c) extensive property |
| (iv) ∆rGCell | (d) increases with dilution |
Match the items of Column I and Column II.
| Column I | Column II |
| (i) K | (a) I × t |
| (ii) Λm | (b) `Λ_m/Λ_m^0` |
| (iii) α | (c) `K/c` |
| (iv) Q | (d) `G^∗/R` |
Standard reduction electrode potentials of three metals A, B and C are respectively + 0.5 V, – 3.0 V. and – 1.2 V. The reducing powers of there metal is.
Given the data at 25°C
\[\ce{Ag + I- -> AgI + e-}\]; E° = – 0.152 V
\[\ce{Ag -> Ag+ + e-}\]; E° = – 0.800 V
The value of log Ksp for AgI is ______.
If the half-cell reaction A + e– → A– has a large negative reduction potential, it follow that:-
In a Daniel cell, ______.
Read the passage given below and answer the questions that follow:
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Oxidation-reduction reactions are commonly known as redox reactions. They involve transfer of electrons from one species to another. In a spontaneous reaction, energy is released which can be used to do useful work. The reaction is split into two half-reactions. Two different containers are used and a wire is used to drive the electrons from one side to the other and a Voltaic/Galvanic cell is created. It is an electrochemical cell that uses spontaneous redox reactions to generate electricity. A salt bridge also connects to the half-cells. The reading of the voltmeter gives the cell voltage or cell potential or electromotive force. If \[\ce{E^0_{cell}}\] is positive the reaction is spontaneous and if it is negative the reaction is non-spontaneous and is referred to as electrolytic cell. Electrolysis refers to the decomposition of a substance by an electric current. One mole of electric charge when passed through a cell will discharge half a mole of a divalent metal ion such as Cu2+. This was first formulated by Faraday in the form of laws of electrolysis.
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- Is silver plate the anode or cathode? (1)
- What will happen if the salt bridge is removed? (1)
- When does electrochemical cell behaves like an electrolytic cell? (1)
- (i) What will happen to the concentration of Zn2+ and Ag+ when Ecell = 0. (1)
(ii) Why does conductivity of a solution decreases with dilution? (1)
OR
The molar conductivity of a 1.5 M solution of an electrolyte is found to be 138.9 S cm2mol-1. Calculate the conductivity of this solution. (2)
The two half cell reaction of an electrochemical cell is given as
\[\ce{Ag+ + e- -> Ag}\], `"E"_("Ag"^+//"Ag")^circ` = - 0.3995 V
\[\ce{Fe^{2+} -> Fe^{3+} + e-}\], `"E"_("Fe"^{3+}//"Fe")^{2+}` = - 0.7120 V
The value of EMF will be ______.
What should be the signs (positive/negative) for \[\ce{E^0_{cell}}\] and ΔG0 for a spontaneous redox reaction occurring under standard conditions?
What is an electrochemical cell? What does it consist of?
