Viraf J Dalal Chemistry Class 8 Icse Solutions -
This is a complete guide to Viraf J. Dalal's ICSE Chemistry for Class 8, including how to find solutions, understand the syllabus, and prepare effectively for exams.
Chapter 4: Atomic Structure
Q1. Name the discoverer of: (a) Electron (b) Proton (c) Nucleus.
Ans:
- (a) Electron: J.J. Thomson
- (b) Proton: Goldstein (discovered canal rays leading to proton discovery) / Rutherford (named it).
- (c) Nucleus: Ernest Rutherford
Q2. Define the term ‘Atomic Number’ and ‘Mass Number’.
Ans:
- Atomic Number (Z): The number of protons present in the nucleus of an atom. It determines the identity of an element.
- Mass Number (A): The sum of the number of protons and neutrons present in the nucleus of an atom ($A = P + N$).
Q3. Calculate the number of neutrons in an atom of $\text^23_11Na$.
Ans: viraf j dalal chemistry class 8 icse solutions
- Mass Number ($A$) = 23
- Atomic Number ($Z$) = 11 (Protons = 11)
- Number of Neutrons = $A - Z = 23 - 11 = \mathbf12$.
Clarity without oversimplification
One of the strengths of Dalal’s approach is linguistic balance. Explanations are concise and accessible, yet they avoid the trap of dumbing down. Definitions are stated precisely; steps in a numerical or experimental solution are sequenced so a learner can reproduce them. For ICSE learners—who must both understand concepts and demonstrate procedure in exams—this balance trains two complementary competencies: conceptual insight and exam-ready technique.
2. Physical and Chemical Changes (Advanced)
A deeper look at energy changes (exothermic vs. endothermic reactions) and the classification of changes.
- Solutions help with: Diagram-based questions for electrolysis, and long-answer questions on the characteristics of chemical reactions (evolution of gas, change of color, etc.).
The Importance of Reference Solutions for Class 8 Chemistry
Many students make the mistake of copying answers directly from solution guides. That is the wrong approach. Here is how you should use these solutions effectively: This is a complete guide to Viraf J
- Attempt First: Solve the "Practice Problems" and "Objective Type Questions" on your own.
- Cross-Verify: Use the solutions to check if your steps are correct, especially for numerical problems based on Gay-Lussac’s Law or percentage composition.
- Understand the Logics: Pay attention to the reasoning provided for multiple-choice questions (MCQs). ICSE exams often test the "reason" behind the "assertion."
- Answer Structure: ICSE examiners award marks for presentation. The solutions teach you how to write precise, keyword-rich answers.
8. Where to Download Complete Solutions PDF
You can find full chapter-wise solutions in one PDF at:
- KnowledgeBoat (search: Viraf Dalal Class 8 Solutions)
- ICSE Solutions (website: icsesolutions.com – has Dalal-specific section)
- LearnInsta (provides free PDFs for Dalal’s ICSE Chemistry 8)
⚠️ Avoid unverified Telegram/WhatsApp groups – many contain incomplete or incorrect answers.
B. Free Online Resources (Reliable)
| Website | What it offers |
|---------|----------------|
| Vedantu | Free PDFs for Dalal Class 8 solutions (chapter-wise) |
| TopperLearning | Some free solutions + premium for detailed answers |
| KnowledgeBoat | Chapter-wise solutions for Dalal’s book |
| ICSE Study Material (various blogs) | Typed solutions for all exercises | Chapter 4: Atomic Structure
Q1
Example search: "Viraf J Dalal Class 8 Chemistry Chapter 3 solutions"
1. About the Book & Author
Book Title: ICSE Chemistry for Class 8
Author: Viraf J. Dalal
Publisher: Allied Publishers (common edition)
Purpose: Follows the latest ICSE syllabus for Class 8 Chemistry. The book is known for clear explanations, diagrams, and a step-by-step approach.
Chapter 3: Elements, Compounds & Mixtures
Q1. Define: (a) Element (b) Compound (c) Mixture.
Ans:
- (a) Element: A pure substance that cannot be broken down into simpler substances by chemical means (e.g., Hydrogen, Gold).
- (b) Compound: A pure substance formed by the chemical combination of two or more elements in a fixed ratio by mass (e.g., Water $H_2O$).
- (c) Mixture: An impure substance made by mixing two or more substances in any ratio without chemical reaction (e.g., Air, Soil).
Q2. Give two differences between Compounds and Mixtures.
Ans:
- Composition: Compounds have a fixed composition; Mixtures have variable composition.
- Properties: Compounds have entirely new properties different from the constituent elements; Mixtures retain the properties of their constituents.
Q3. Classify the following into Elements, Compounds, and Mixtures:
- (a) Air: Mixture
- (b) Mercury: Element
- (c) Water: Compound
- (d) Brass: Mixture
- (e) Sodium Chloride: Compound