Electrochemistry Class 12 NCERT solutions provide step-by-step answers to textbook questions, helping students grasp concepts like electrolysis, galvanic cells, and conductivity. These expert-backed solutions simplify complex topics, ensuring a strong foundation for exams. Ideal for CBSE students, they enhance problem-solving skills and conceptual clarity. Download the latest NCERT solutions for free.
Section 1: Fundamentals of Electrochemistry
Q1: What is electrochemistry?
A: Electrochemistry is the study of the interconversion of electrical energy and chemical energy through redox reactions.
Q2: Define oxidation and reduction in terms of electron transfer.
A:
Q3: What is an electrochemical cell?
A: An electrochemical cell is a device that generates electricity through a redox reaction or uses electrical energy to drive a chemical reaction.
Q4: Differentiate between an electrolytic cell and a galvanic cell.
A:
Q5: What is electrode potential?
A: Electrode potential is the potential difference between an electrode and its solution.
Section 2: Electrochemical Cells
Q6: Explain the working of a Daniel cell.
A: The Daniel cell consists of a zinc electrode in ZnSO₄ solution and a copper electrode in CuSO₄ solution. Zinc undergoes oxidation, and copper undergoes reduction, generating an electric current.
Q7: What is a salt bridge?
A: A salt bridge is used in electrochemical cells to maintain electrical neutrality by allowing the movement of ions.
Q8: Write the overall reaction of a Daniel cell.
A: Zn (s) + Cu²⁺ (aq) → Zn²⁺ (aq) + Cu (s)
Q9: What is the standard hydrogen electrode (SHE)?
A: SHE is a reference electrode with an assigned potential of 0.00V.
Q10: What is the function of the salt bridge in a galvanic cell?
A: It prevents charge buildup by allowing ion flow between the two half-cells.
Section 3: Nernst Equation and Conductance
Q11: State the Nernst equation.
A: The Nernst equation calculates the electrode potential at non-standard conditions: E = E° - (0.0591/n) log [oxidized form]/[reduced form]
Q12: What is the importance of the Nernst equation?
A: It helps determine the cell potential under varying concentrations.
Q13: Define conductance in electrolytes.
A: Conductance is the ability of an electrolyte to conduct electricity.
Q14: What is the SI unit of conductance?
A: The SI unit is Siemens (S).
Q15: How does molar conductivity vary with dilution?
A: Molar conductivity increases with dilution.
Section 4: Electrolysis and Faraday's Laws
Q16: What is electrolysis?
A: Electrolysis is the process of passing an electric current through an electrolyte to bring about a chemical reaction.
Q17: State Faraday’s first law of electrolysis.
A: The mass of a substance deposited at an electrode is directly proportional to the quantity of electricity passed.
Q18: State Faraday’s second law of electrolysis.
A: When the same quantity of electricity is passed through different electrolytes, the masses of substances deposited are proportional to their equivalent weights.
Q19: What is the electrochemical equivalent of an element?
A: The electrochemical equivalent is the mass of a substance deposited per coulomb of charge.
Q20: What is the role of an electrolyte in electrolysis?
A: An electrolyte provides ions that undergo redox reactions at the electrodes.
Section 5: Applications of Electrochemistry
Q21: What are fuel cells?
A: Fuel cells are electrochemical cells that convert chemical energy directly into electrical energy.
Q22: Give an example of a fuel cell.
A: The hydrogen-oxygen fuel cell.
Q23: What is corrosion?
A: Corrosion is the gradual destruction of metals due to chemical reactions with the environment.
Q24: How can corrosion be prevented?
A: By galvanization, coating, or using cathodic protection.
Q25: What is the significance of electroplating?
A: Electroplating enhances the appearance and resistance of metals to corrosion.
Additional Questions
Q26: Why is a platinum electrode used in a standard hydrogen electrode?
A: Platinum is inert and provides a surface for the hydrogen gas reaction.
Q27: What is a primary cell?
A: A primary cell is a non-rechargeable electrochemical cell (e.g., dry cell).
Q28: What is a secondary cell?
A: A secondary cell is a rechargeable electrochemical cell (e.g., lead-acid battery).
Q29: What are redox reactions?
A: Redox reactions involve simultaneous oxidation and reduction.
Q30: What is an anode and a cathode?
A:
Practice Questions
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Define standard electrode potential.
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Write two examples of electrolytic cells used in daily life.
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How is electrolysis used in the purification of metals?
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Explain the working of the lead-acid battery.
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What is the difference between a battery and a fuel cell?
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Why is a salt bridge necessary in a galvanic cell?
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What are the disadvantages of corrosion?
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How does temperature affect conductivity?
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Write the reaction occurring at the electrodes of a dry cell.
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What is the role of the diaphragm in an electrolytic cell?
Best Books for Electrochemistry (Class 12 NCERT Solutions)
Here is a curated list of books covering Electrochemistry for Class 12, along with details on the type of content and questions included in each.
1. NCERT Exemplar Problems – Chemistry (Class 12)
- Author: NCERT
- Publication: NCERT
- Content: Advanced-level questions based on NCERT concepts, including MCQs, Assertion-Reason, and Case-Based Questions for better conceptual clarity.
2. Pradeep’s New Course Chemistry (Class 12)
- Author: S. N. Dhawan, S. C. Kheterpal, P. N. Kapil
- Publication: Pradeep Publications
- Content: Topic-wise theory with solved and unsolved numerical problems, conceptual questions, and previous year board exam questions.
3. Arihant All in One Chemistry Class 12
- Author: Arihant Experts
- Publication: Arihant Publications
- Content: Detailed NCERT-based explanations, step-by-step NCERT solution approach, conceptual MCQs, reasoning-based, and HOTS questions.
4. Modern’s ABC of Chemistry (Class 12)
- Author: Dr. S. P. Jauhar
- Publication: Modern Publishers
- Content: Elaborate explanations of electrochemistry concepts, competitive exam-level questions, and NCERT solution breakdowns.
5. Concise Chemistry Class 12
- Author: R.P. Rana
- Publication: Selina Publishers
- Content: Conceptual breakdown with short answer questions, long answer questions, and numerical problem-solving strategies.
6. GRB Chemistry for Class 12
- Author: O. P. Tandon
- Publication: GRB Publications
- Content: In-depth theoretical concepts, solved numerical problems, reasoning-based questions, assertion-reason, and case study-based questions.
7. Dinesh Chemistry Class 12
- Author: P.N. Kapil
- Publication: S. Dinesh & Co.
- Content: Step-by-step solutions to NCERT questions, additional theory for competitive exams, previous year board questions.
8. Cengage Chemistry Class 12
- Author: K.S. Verma
- Publication: Cengage Learning
- Content: Illustrative examples, numerical problem-solving, practice exercises, and concept application questions.
9. MTG NCERT Fingertips Chemistry (Class 12)
- Author: MTG Editorial Board
- Publication: MTG Learning Media
- Content: NCERT-based objective questions, conceptual MCQs, assertion-reason, and board-level practice questions.
10. Trueman’s Elementary Chemistry for Class 12
- Author: K.L. Kapoor
- Publication: Trueman Book Company
- Content: Chapter-wise NCERT-based explanations, topic-wise questions, numerical practice, and exam-oriented problem sets.
11. VK Chemistry (Class 12)
- Author: Dr. Rajeev Bansal
- Publication: VK Global Publications
- Content: Includes concept-based and competitive-level questions, detailed NCERT solutions, and practice numericals.
12. Narendra Awasthi Physical Chemistry
- Author: Narendra Awasthi
- Publication: Balaji Publications
- Content: Advanced physical chemistry numerical problems, including electrochemistry numerical practice for JEE and board exams.
13. Problems in Physical Chemistry
- Author: P. Bahadur
- Publication: G.R. Bathla Publications
- Content: Numerical-based approach, with detailed solutions to NCERT electrochemistry numericals and conceptual derivations.
14. Concepts of Physical Chemistry
- Author: P. Bahadur
- Publication: G.R. Bathla Publications
- Content: Focuses on numerical problem-solving, electrochemical series, Nernst equation, and Gibbs free energy calculations.
15. NCERT Solutions for Class 12 Chemistry
- Author: Oswaal Editorial Board
- Publication: Oswaal Books
- Content: Chapter-wise NCERT solutions, board exam questions, concept-based explanations, and practice exercises.
16. Physical Chemistry for JEE and NEET
- Author: R. K. Gupta
- Publication: Arihant Publications
- Content: Includes electrochemistry MCQs, competitive exam-level numericals, and NCERT topic-based theory.
17. Comprehensive Chemistry Class 12
- Author: Dr. N. K. Verma
- Publication: Laxmi Publications
- Content: NCERT topic explanations, multiple-choice questions, short and long answer questions, and numerical-based questions.
18. Target Publications Chemistry Class 12
- Author: Target Experts
- Publication: Target Publications
- Content: Topic-wise explanations, practice exercises, numerical problems, and board-oriented questions.
19. Understanding Chemistry for Class 12
- Author: Dr. N.K. Verma
- Publication: New Age International Publishers
- Content: Theory with illustrations, practice numericals, reasoning-based questions, and chapter-end quizzes.
20. Xam Idea Chemistry Class 12
- Author: Xam Idea Editorial Team
- Publication: VK Global Publications
- Content: NCERT-based questions, board pattern sample papers, conceptual MCQs, and numerical problem sets.
Key Topics Covered in Class 12 Electrochemistry NCERT Solutions
The chapter on Electrochemistry in Class 12 NCERT Chemistry includes:
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Electrochemical Cells
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Galvanic and Electrolytic Cells
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Nernst Equation
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Conductance of Electrolytic Solutions
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Kohlrausch’s Law
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Batteries and Fuel Cells
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Corrosion and its Prevention
The NCERT solutions provide well-structured answers to textbook problems, helping students build a strong conceptual foundation.
Electrochemical Cells: Understanding the Basics
An electrochemical cell converts chemical energy into electrical energy through spontaneous redox reactions. The two main types are:
NCERT solutions offer a step-by-step explanation of these cells with proper diagrams, making it easier for students to grasp their working principles.
Nernst Equation: Application and Importance
The Nernst equation is a crucial concept in electrochemistry, helping to determine the electrode potential under non-standard conditions. The equation is given by:
where:
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E = Electrode potential
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E⁰ = Standard electrode potential
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R = Gas constant
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T = Temperature in Kelvin
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n = Number of electrons transferred
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F = Faraday’s constant
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Q = Reaction quotient
NCERT solutions provide clear derivations and examples to illustrate its practical applications.
Conductance of Electrolytic Solutions
Electrical conductivity in electrolytes depends on:
Key terms explained in NCERT solutions include:
Understanding these concepts helps students in solving numerical problems effectively.
Kohlrausch’s Law and its Applications
Kohlrausch’s Law states that the limiting molar conductivity of an electrolyte can be represented as the sum of the individual contributions of its ions. This principle is used to:
NCERT solutions provide insightful derivations and practice problems for students to strengthen their understanding.
Batteries and Fuel Cells
Batteries and fuel cells are practical applications of electrochemistry. The NCERT textbook covers:
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Primary Batteries: Non-rechargeable, e.g., Dry Cell
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Secondary Batteries: Rechargeable, e.g., Lead-Acid Battery, Lithium-Ion Battery
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Fuel Cells: Highly efficient energy sources, e.g., Hydrogen-Oxygen Fuel Cell
Solutions offer well-explained diagrams and comparisons, ensuring a better grasp of the topic.
Corrosion and its Prevention
Corrosion is the gradual deterioration of metals due to chemical reactions with the environment. The most common example is rusting of iron. NCERT solutions help students understand:
Why NCERT Solutions Are Essential for Electrochemistry Preparation
1. Conceptual Clarity
NCERT solutions provide detailed explanations, enabling students to understand the fundamentals of electrochemistry in a structured manner.
2. Step-by-Step Solutions
Each problem is solved methodically, helping students learn the approach to solving numerical and theoretical questions effectively.
3. Board Exam and Competitive Exam Relevance
Electrochemistry questions frequently appear in board exams, JEE, NEET, and other entrance tests. NCERT solutions offer the best preparation by covering all essential topics in detail.
4. Practice Problems for Mastery
NCERT exercises include multiple conceptual and numerical questions that reinforce learning and problem-solving skills.
Expert Tips for Mastering Electrochemistry
1. Understand the Basics First
Before diving into numericals, grasp the fundamental concepts of oxidation-reduction reactions, electrode potential, and electrochemical cells.
2. Memorize Key Equations
Equations like the Nernst equation, conductivity formulas, and Faraday’s laws are crucial. Regular revision ensures better retention.
3. Solve NCERT Examples and Exercises
Attempt all NCERT in-text and exercise problems to build confidence in solving questions efficiently.
4. Revise Using Flowcharts and Diagrams
Electrochemistry involves several interconnected concepts. Using diagrams, tables, and flowcharts makes revision easier.
5. Solve Previous Year Questions
Practicing previous board exam and competitive exam questions helps in understanding the question patterns and improving time management.