Class 9 Science Chapter 8 Journey Inside the Atom – Latest Concept Clarity MCQs with Answers | New NCERT Book 2026–27 Edition

   Welcome to our Class 8 Journey Inside the Atom Concept Clarity MCQs with Answers. This practice set contains latest MCQs based on the new NCERT Class 9 Science Book 2026–27 Edition and is designed to help students strengthen their understanding of important concepts related to the structure of atoms, subatomic particles, atomic models, and the arrangement of electrons in an atom.

These concept-based MCQs focus on understanding rather than memorisation, helping students test their conceptual clarity and identify areas that need improvement. The questions are ideal for Class 9 students preparing for school examinations, revision, and concept-based assessments according to the latest NCERT textbook and syllabus for the 2026–27 academic session.

Journey Inside the Atom Current Concept Clarity MCQs with Answers:-

Q1. Which statement best explains why an atom is electrically neutral?

a) Protons are absent
b) Neutrons cancel electrons
c) Protons equal electrons
d) Electrons equal neutrons

Q2. An atom has 11 protons and 10 electrons. What is its charge?

a) -1
b) 0
c) +1
d) +2

Q3. Which particle determines the atomic number of an element?

a) Electron
b) Proton
c) Neutron
d) Nucleus

Q4. Two atoms of the same element have different numbers of neutrons. They are called:

a) Ions
b) Isotopes
c) Molecules
d) Cations

Q5. Which particle contributes most to the mass of an atom?

a) Electron
b) Proton
c) Neutron
d) Both b and c

Q6. Most alpha particles passed straight through the gold foil because:

a) Nucleus is large
b) Atom is mostly empty
c) Electrons are heavy
d) Gold is transparent

Q7. What is the maximum number of electrons that can occupy the K shell?

a) 1
b) 2
c) 8
d) 18

Q8. An atom has electronic configuration 2, 8, 1. Its valency is:

a) 1
b) 2
c) 7
d) 8

Q9. An element has 17 electrons. How many electrons are present in its outermost shell?

a) 1
b) 5
c) 7
d) 8

Q10. If the atomic number is 13 and mass number is 27, the number of neutrons is:

a) 13
b) 14
c) 27
d) 40

Q11. Which pair represents isotopes of the same element?

a) 6p, 6n and 7p, 6n
b) 8p, 8n and 8p, 10n
c) 7p, 7n and 8p, 8n
d) 9p, 10n and 10p, 9n

Q12. Which observation of Rutherford"s gold foil experiment was especially difficult for Thomson’s model to explain?

a) Most particles passed through
b) Some particles bounced back
c) Alpha particles were charged
d) Gold foil was very thin  

Q13. According to Rutherford, most of an atom consists of:

a) Protons
b) Neutrons
c) Empty space
d) Electrons

Q14. The major limitation of Rutherford’s model was that it could not explain:

a) Atomic mass
b) Atomic stability
c) Positive charge
d) Existence of nucleus

Q15. Why should an electron in Rutherford’s model lose energy?

a) It is neutral
b) It is accelerating
c) It is stationary
d) It has no mass

Q16. The neutron was discovered by:

a) J. J. Thomson
b) Ernest Rutherford
c) Niels Bohr
d) James Chadwick

Q17. Protons and neutrons together are called:

a) Electrons
b) Ions
c) Nucleons
d) Isotopes

Q18. Bohr’s shells are also known as:

a) Mass levels
b) Energy levels
c) Charge levels
d) Nuclear levels

Q19. As the distance from the nucleus increases, electron energy generally:

a) Decreases
b) Remains same
c) Increases
d) Becomes zero

Q20. The energy absorbed or released during a shell transition equals:

a) Total atomic mass
b) Difference between energy levels
c) Atomic number
d) Number of neutrons

Q21. An element with fewer than four valence electrons generally tends to:

a) Gain electrons
b) Lose electrons
c) Gain neutrons
d) Lose protons

Q22. Which quantity uniquely identifies an element?

a) Number of shells
b) Number of neutrons
c) Atomic number
d) Mass number

Q23. Which pair represents isobars?

a) ³⁵₁₇Cl and ³⁷₁₇Cl
b) ⁴⁰₁₈Ar and ⁴⁰₂₀Ca
c) ¹²₆C and ¹³₆C
d) ¹H and ²H

Q24. Why is chlorine’s average atomic mass not exactly 36 u?

a) Protons have different charges
b) Chlorine has no isotopes
c) Electrons have no mass
d) Isotopes have unequal abundance

Q25. Isotopes of an element have similar chemical properties mainly because they have the same:

a) Number of neutrons
b) Mass number
c) Electronic configuration
d) Nuclear mass

🧠 TopperGuru1 Concept Check

Before checking the answer key, ask yourself these two questions for every MCQ:

✅ Why is the correct option right?

✅ Why are the other three options wrong?

If you can explain both, your concept is truly clear. If not, revise the related NCERT concept and try again.

Remember: Real learning happens when you understand the reason, not when you memorize the answer. 

Answer Key:-

1 c, 2. c, 3. b, 4. b, 5. d, 6. b, 7. b, 8. a, 9. c, 10. b, 11. b, 12. b, 13. c, 14. b, 15. b, 16. d, 17. c, 18. b, 19. c, 20. b, 21. b, 22. c, 23. b, 24. d, 25. c,

Class 9 Science Chapter 8 Journey Inside the Atom MCQs – Keep Practising!

We hope these Class 9 Science Chapter 8 Journey Inside the Atom MCQs with Answers helped you test your conceptual understanding of the chapter. These latest concept clarity MCQs are based on the new NCERT Class 9 Science Book 2026–27 Edition and are designed to strengthen your concepts and prepare you for exams.

How many questions did you answer correctly? Check your answers using the answer key above and revise the concepts where you made mistakes.

Keep practising with TopperGuru1 for more Class 9 Science MCQs, concept clarity questions, and chapter-wise practice questions with answers based on the latest NCERT syllabus.

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