The cathode reaction in the dry cell will be
- $\ce{ Zn_{(s)} -> Zn^{2+} + 2e^- }$
- $\ce{ MnO_2 + NH^+_4 + e^- -> MnO(OH) + NH_3}$
- $\ce{ Zn(Hg) + 2OH^- -> ZnO_{(s)} + H_2O + 2e^-}$
- $\ce{MnO(OH) + NH_3 - -> MnO_2 + NH^+_4 + 2e^- }$
The Correct Option is B
Solution and Explanation
Top Questions on Galvanic Cells
- Which of the following reactions correctly represents a Daniell Cell?
- CUET (PG) - 2025
- Chemistry
- Galvanic Cells
- \( E^\circ_{\text{Cell}} = 1.1 \, \text{V}. \, \text{Find} \, E_{\text{Cell}} \, \text{for the reaction:} \, \text{Zn} + \text{Cu}^{2+} \, (0.1M) \rightleftharpoons \text{Zn}^{2+} \, (0.001M) + \text{Cu} \)
- KEAM - 2025
- Chemistry
- Galvanic Cells
- If one faraday of electricity is used in the discharging of \(Cu^{2+}\), then find the mass (ing) of \(Cu\) deposited (nearest integer)
- JEE Main - 2024
- Chemistry
- Galvanic Cells
- In which of the following Galvanic cells, emf is maximum? (Given: \( E^\circ_{\text{Mg}} = -2.36 \, V \) and \( E^\circ_{\text{Cl}_2/\text{Cl}^-} = +1.36 \, V \))
- AP EAMCET - 2024
- Chemistry
- Galvanic Cells
Calculate the EMF of the Galvanic cell: $ \text{Zn} | \text{Zn}^{2+}(1.0 M) \parallel \text{Cu}^{2+}(0.5 M) | \text{Cu} $ Given: $ E^\circ_{\text{Zn}^{2+}/\text{Zn}} = -0.763 \, \text{V} $ and $ E^\circ_{\text{Cu}^{2+}/\text{Cu}} = +0.350 \, \text{V} $
- Tripura JEE - 2024
- Chemistry
- Galvanic Cells
Questions Asked in COMEDK UGET exam
- Given that the freezing point of benzene is $ 5.48^\circ C $ and its $ K_f $ value is $ 5.12^\circ C/m $, what would be the freezing point of a solution of 20 g of propane in 400 g of benzene?
- COMEDK UGET - 2024
- Colligative Properties
200 ml of an aqueous solution contains 3.6 g of Glucose and 1.2 g of Urea maintained at a temperature equal to 27$^{\circ}$C. What is the Osmotic pressure of the solution in atmosphere units?
Given Data R = 0.082 L atm K$^{-1}$ mol$^{-1}$
Molecular Formula: Glucose = C$_6$H$_{12}$O$_6$, Urea = NH$_2$CONH$_2$- COMEDK UGET - 2024
- Colligative Properties
- An inorganic compound W undergoes the following reactions: $ W + \text{Na}_2\text{CO}_3 \xrightarrow{\text{O}_2 / \text{heat}} X + H^+ \xrightarrow{} Y(s) $ $ Y(aq) + \text{KCl} (aq) \xrightarrow{} Z(s) $ Z appears in the form of orange crystals and is used as an oxidising agent in acid medium. Identify the compound W.
- COMEDK UGET - 2024
- coordination compounds
- A current of 3.0 A is passed through 750 ml of 0.45 M solution of CuSO₄ for 2 hours with a current efficiency of 90\%. If the volume of the solution is assumed to remain constant, what would be the final molarity of CuSO₄ solution?
- COMEDK UGET - 2024
- Solutions
- For a reaction $ 5X + Y \to 3Z $, the rate of formation of Z is $ 2.4 \times 10^{-5} \, \text{mol L}^{-1} \text{s}^{-1} $. Calculate the average rate of disappearance of X.
- COMEDK UGET - 2024
- Stoichiometry and Stoichiometric Calculations
Concepts Used:
Galvanic Cells
Galvanic cells, also known as voltaic cells, are electrochemical cells in which spontaneous oxidation-reduction reactions produce electrical energy. It converts chemical energy to electrical energy.
It consists of two half cells and in each half cell, a suitable electrode is immersed. The two half cells are connected through a salt bridge. The need for the salt bridge is to keep the oxidation and reduction processes running simultaneously. Without it, the electrons liberated at the anode would get attracted to the cathode thereby stopping the reaction on the whole.
Working Principle Of Galvanic Cell:
- Take two beakers containing electrolytic solutions of copper sulphate and zinc sulphate are taken. It is connected via a salt bridge containing an aqueous solution of potassium chloride.
- Zinc and copper electrodes are immersed in the respective electrodes and connected through a voltmeter to measure the electrical potential.
- Zinc which acts as the anode readily undergoes an oxidation process and acquires a negative charge.
- The electrons travel through the salt bridge and undergo a reduction process at the copper cathode.
- Thus the cathode would acquire a positive charge.
- This flow of electrons from the anode to the cathode induces a flow of electric current in the opposite direction which shall be measured by the voltmeter.
Types of Voltaic Cell:
- Primary Cell
- Dry Cell
- Mercury Cell
- Alkaline Cell
- Secondary Cell
- Nickel-Cadmium Cell
- Lead-Acid Cell
- Lithium-Ion Cell