Qualitative Chemistry Knowledge-based Questions Bank
Welcome to qChem+, your trusted learning partner for NCTB HSC Chemistry! Chapter 2 of Chemistry 1st Paper — Qualitative Chemistry — is one of the most vital chapters for both HSC Board Exams and University Admission Tests (Engineering, Medical, and Public Universities).
In HSC Board examinations, Knowledge-based questions (1-mark questions) test your core fundamental definitions, formulas, laws, and symbols. Scoring full marks in these questions is the key to securing an A+ in Chemistry!
To help NCTB HSC English Version students excel, we have compiled and solved all the authentic knowledge questions from past Board Exams (2015–2026).
Check out the post below to get all these board exam questions along with their correct answers:
📌 1. Atomic Models & Fundamental Particles
1. What is an Isotone?
[SB 17]
2. What is an Isotope?
[MB 25; RB 19; SB 17; RB 15]
3. What is an α-particle (Alpha particle)?
[BB 25; CB 23; RB 22; CB 21; RB 19; CtgB, SB 17; RB 16; SB 16]
📌 2. Quantum Numbers & Orbitals
4. What is a Quantum Number?
[MdB 26; Md(I)B 26; RB 25; DB 22; DinB, CtgB 21; JB, BB 16]
5. What is a Magnetic Quantum Number?
[CB 21]
6. What is a Sub-shell (Sub-energy level)?
[JB 17]
7. What is an Orbit?
[MB 25; RB 22; DinB 21; CtgB 17; JB 15]
8. What is a Node (Nodal Plane)?
[CtgB 26; SB 21; DinB 19]
9. What is an Orbital?
[CtgB, BB 25; CtgB, MB, CB 23; MB, JB 22; DB, RB 21; BB 19; DB, RB, CB 17; SB 16]
📌 3. Rules of Electronic Configuration
10. Write down the electronic configuration of Fe³⁺.
[SB 21]
11. What is the Aufbau Principle?
[MdB 26; CB 22; JB 21; RB 17]
12. What is Hund’s Rule?
[All.B 26; Md(I)B 26; DB, RB 25; DB, DinB, CtgB, BB 23; MB, JB, BB 22; SB 21; RB, JB 19; DinB 17]
13. State Pauli’s Exclusion Principle.
[MB 23; SB 22; RB 21; CtgB 19; RB, JB, SB 17; RB, CB, CtgB 15]
📌 4. Electromagnetic Spectrum & Radiation
14. What is a Spectrum?
[CB, SB 25; CtgB, JB 22; RB, CB, CtgB, BB 18]
15. What is Electromagnetic Radiation?
[SB 22]
16. What is an Electromagnetic Spectrum?
[JB 25]
17. What is a Line Spectrum (Atomic Emission Spectrum)?
[DB 25; RB 23]
18. What is the Stark Effect?
[JB 25]
19. Write down the wavelength range of visible light.
[RB 17]
20. What is the Zeeman Effect?
[DinB 25; DB, MB 21]
21. What is Phosphorescence?
[DinB 25; JB 17]
📌 5. Solubility, Solubility Product & Ionic Product
22. What is a Saturated Solution?
[RB 23]
23. What is the Common Ion Effect?
[DB 16]
24. What is Ionic Product (Kᵢₚ)?
[DB, BB 25; DinB, BB 22; JB 17]
25. What is Solubility Product (Kₛₚ)?
[RB 25; DinB 22; DB 21; DinB 17]
26. What is Solubility?
[Md(I)B 26; SB, BB 22; RB 21; DB, CB, SB 17; RB, BB 15]
📌 6. Qualitative Chemical Analysis & Separation Techniques
27. What is Nessler’s Reagent?
[RB 25; DinB, CtgB 22; JB 21; RB 17]
28. What is Crystallization?
[MB, CtgB 21; DinB 19]
29. What is Fractional Distillation?
[JB 19; CB, CtgB, BB 18; SB 15; CB 17]
30. What is Steam Distillation?
[CtgB 26; DB 19]
31. What is Solvent Extraction?
[CB 19; SB 15]
32. What is Vacuum Distillation (Distillation under reduced pressure)?
[DinB 17]
33. What is Chromatography?
[CtgB 19; CB, CtgB, BB 18; CtgB 16; RB, BB 15]
34. What is Retention Factor (R𝒇)?
[All.B 26; SB 19; SB 17; DinB 15]
Abbreviations used: All.B = All Board, DB = Dhaka, RB = Rajshahi, CB = Comilla, JB = Jessore, CtgB = Chittagong, BB = Barisal, SB = Sylhet, DinB = Dinajpur, MB = Mymensingh, MdB = Madrasah, Md(I)B = Madrasah (Irregular).
💡 Top Exam Preparation Tips from qChem+:
- Practice Board Tagged Questions: Revise these 34 core questions repeatedly — they represent over 90% of the recurring knowledge-based questions in HSC Board Exams.
- Pay Attention to Symbols & Charges: Ensure accurate representation of chemical formulas, charges (e.g., Fe³⁺, He²⁺, NH₄⁺), quantum numbers, and mathematical expressions.
- Bookmark & Share: Keep qChem+ bookmarked for more English Version HSC Chemistry study notes, board solutions, and admission prep resources!
Are you looking for the Bangla version of this post? Visit the link below:
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