Advertisements
Advertisements
प्रश्न
Can you store copper sulphate solutions in a zinc pot?
Advertisements
उत्तर
\[\ce{E^Θ_{{Zn^{2+}/{ Zn}}}}\] = −0.76 V; \[\ce{E^Θ_{{Cu^{2+}/{ Cu}}}}\] = 0.34 V
We have to check whether the following reaction takes place or not.
\[\ce{Zn_{(s)} + CuSO4_{(aq)} -> ZnSO4_{(aq)} + Cu_{(s)}}\]
The cell can be represented as:
\[\ce{Zn | Zn^{2+} || Cu^{2+} | Cu}\]
\[\ce{E^Θ_{cell} = E^Θ_{{Cu^{2+}/{ Cu}}} - E^Θ_{{Zn^{2+}/{ Zn}}}}\]
= 0.34 V – (–0.76 V)
= 1.1 V
Since \[\ce{E^Θ_{cell}}\] is positive, the reaction takes place, and we cannot store \[\ce{CuSO4}\] solution in a zinc pot.
APPEARS IN
संबंधित प्रश्न
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 \[\ce{Zn}\]
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)
E°cell for the given redox reaction is 2.71 V
Mg(s) + Cu2+ (0.01 M) → Mg2+ (0.001 M) + Cu(s)
Calculate Ecell for the reaction. Write the direction of flow of current when an external opposite potential applied is
(i) less than 2.71 V and
(ii) greater than 2.71 V
Assertion: pure iron when heated in dry air is converted with a layer of rust.
Reason: Rust has the compositionFe3O4.
A certain current liberated 0.504 gm of hydrogen in 2 hours. How many grams of copper can be liberated by the same current flowing for the same time through copper sulphate solution.
Describe the construction of Daniel cell. Write the cell reaction.
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
Two metals M1 and M2 have reduction potential values of −xV and +yV respectively. Which will liberate H2 and H2SO4.
Which of the following statement is not correct about an inert electrode in a cell?
An electrochemical cell can behave like an electrolytic cell when ______.
What is electrode potential?
Consider a cell given below:
\[\ce{Cu | Cu^{2+} || Cl^{-} | Cl_{2},Pt}\]
Write the reactions that occur at anode and cathode
Which of the following statements about galvanic cell is incorrect
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.
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)
In a solution of CuSO4, how much time will be required to precipitate 2 g copper by 0.5 ampere current?
Explain why the anode is of negative polarity in a galvanic cell.
Explain the types of electrochemical cells.
State the term for the following:
Two metal plates or wires through which the current enters and leaves the electrolytic cell.
