Advertisements
Advertisements
Question
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?
Advertisements
Solution
When the opposing potential becomes equal to electrical potential, the cell reaction stops and no current flows through the cell. Thus, there is no chemical reaction.
APPEARS IN
RELATED QUESTIONS
Can you store copper sulphate solutions in a zinc pot?
Among Zn and Cu, which would occur more readily in nature as metal and which as an ion?
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?
Zinc can be coated on iron to produce galvanized iron but the reverse is not possible. It is because ____________.
A gas X at 1 atm is bubbled through a solution containing a mixture of 1 MY− and 1 MZ− at 25°C. If the reduction potential of Z > Y > X, then ______.
Can Fe3+ oxidises bromide to bromine under standard conditions?
Given: \[\ce{E^0_{{Fe^{3+}|Fe^{2+}}}}\] = 0.771 V
\[\ce{E^0_{{Br_{2}|Br^-}}}\] = −1.09 V
Write a note on sacrificial protection.
The quantity of charge required to obtain one mole of aluminium from Al2O3 is ______.
How will the pH of brine (aq. \[\ce{NaCl}\] solution) be affected when it is electrolysed?
Consider a cell given below:
\[\ce{Cu | Cu^{2+} || Cl^{-} | Cl_{2},Pt}\]
Write the reactions that occur at anode and cathode
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` |
Assertion: ECell should have a positive value for the cell to function.
Reason: `"E"_("cathode") < "E"_("anode")`
If the half-cell reaction A + e– → A– has a large negative reduction potential, it follow that:-
Read the passage given below and answer the questions that follow:
|
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.
|
- 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)
On which electrode the oxidation reaction takes place?
Which of the following is incorrect?
Galvanic cell is a device in which ______.
Calculate the λ0m for Cl- ion from the data given below:
∧0m MgCl2 = 258.6 Scm2 mol-1 and λ0m Mg2+ = 106 Scm2 mol-1
Explain why the anode is of negative polarity in a galvanic cell.

