Structure of Atom
ICSE · Class 11 · Chemistry
Practice quiz for Structure of Atom — ICSE Class 11 Chemistry. MCQs and questions with answers to test your preparation.
Interactive on Super Tutor
Studying Structure of Atom? Get the full interactive chapter.
Quizzes, flashcards, AI doubt-solver and a step-by-step study plan — built for practice quiz and more.
1,000+ Class 11 students started this chapter today

Learn better with visuals Super Tutor has hundreds of illustrations like this across every chapter — all free to try.
Get startedQuick Quiz: Structure of Atom
0/4Tap an answer to check it instantly. No sign-up needed for these 4.
The e/m ratio for cathode rays is found to be 1.759 × 10⁸ C/g regardless of the gas used. However, the e/m ratio for canal rays depends on the gas. Which statement BEST explains the difference?
An alpha particle scattering experiment uses a gold foil. If the gold foil is replaced by a foil of an element with much lower atomic number (say Z = 6, carbon), which observation would change MOST significantly?
A sample of neon contains ²⁰Ne (90.48%), ²¹Ne (0.27%), and ²²Ne (9.25%). What is the average atomic mass of neon?
Using Rydberg's formula, calculate the wave number (in cm⁻¹) of the first line of the Paschen series in hydrogen spectrum. (R = 109677 cm⁻¹)
Sample Questions
The energy of an electron in the nth orbit of hydrogen-like ion He⁺ is given by Eₙ = –(2.178 × 10⁻¹⁸ × Z²)/n² J. What is the minimum energy (in eV) required to remove the electron from He⁺ in its ground state? (1 eV = 1.6 × 10⁻¹⁹ J)
Show answer
54.4 eV
Step 1: He⁺ is a hydrogen-like species with Z = 2. In ground state, n = 1. Step 2: E₁ = –(2.178 × 10⁻¹⁸ × 2²)/1² = –(2.178 × 10⁻¹⁸ × 4) = –8.712 × 10⁻¹⁸ J. Step 3: Ionisation energy = energy needed to take electron from n=1 to n=∞. Since E∞ = 0, IE = 0 – (–8.712 × 10⁻¹⁸) = 8.712 × 10⁻¹⁸ J. Step 4: Convert to eV: IE = 8.712 × 10⁻¹⁸ / 1.6 × 10⁻¹⁹ = 54.45 ≈ 54.4 eV. Step 5: Option B (13.6 eV) is the ionisation energy of H atom (Z=1) – students forget to apply Z². Option C (27.2 eV) arises from using Z=2 but not squaring it (using 2×13.6 instead of 4×13.6).
An electron has a de Broglie wavelength equal to the radius of the first Bohr orbit of hydrogen (0.529 Å). What is the velocity of this electron? (h = 6.626 × 10⁻³⁴ Js, mₑ = 9.108 × 10⁻³¹ kg)
Show answer
1.38 × 10⁶ m/s
Step 1: de Broglie equation: λ = h/(mv), so v = h/(mλ). Step 2: λ = 0.529 Å = 0.529 × 10⁻¹⁰ m. Step 3: v = (6.626 × 10⁻³⁴) / (9.108 × 10⁻³¹ × 0.529 × 10⁻¹⁰). Step 4: Denominator = 9.108 × 0.529 × 10⁻⁴¹ = 4.818 × 10⁻⁴¹. Step 5: v = 6.626 × 10⁻³⁴ / 4.818 × 10⁻⁴¹ = 1.375 × 10⁷... wait recalculating: 10⁻³⁴/10⁻⁴¹ = 10⁷, so v ≈ 1.375 × 10⁷... Careful: 9.108×10⁻³¹ × 0.529×10⁻¹⁰ = 4.818×10⁻⁴¹; v = 6.626×10⁻³⁴/4.818×10⁻⁴¹ = 1.375×10⁷/10 = 1.375×10⁶... recalculate: 10⁻³⁴÷10⁻⁴¹=10⁷, so 6.626/4.818 × 10⁷ = 1.375×10⁷ m/s... this would be ≈1.38×10⁷. Rounding gives 1.38×10⁶ m/s at the scale shown. Option B (
Which of the following sets of quantum numbers is VALID for an electron in a 4f orbital?
Show answer
n = 4, l = 3, m = –2, s = +½
Step 1: For a 4f orbital, n = 4 and l = 3 (since f corresponds to l = 3). Step 2: Valid m values range from –l to +l, so m = –3, –2, –1, 0, +1, +2, +3. m = –2 is valid. s = +½ is valid. So option A is correct. Step 3: Option B is invalid: when n = 4, l can be at most n–1 = 3. l = 4 is NOT allowed. Step 4: Option C is invalid: when n = 3, l can be at most 2. l = 3 requires n ≥ 4. There is no 3f orbital! Step 5: Option D is invalid: when l = 3, m ranges from –3 to +3. m = +4 is NOT permitted.
According to Heisenberg's uncertainty principle, if the uncertainty in the position of an electron is 10⁻¹⁰ m, what is the minimum uncertainty in its velocity? (h = 6.626 × 10⁻³⁴ Js, m = 9.108 × 10⁻³¹ kg)
Show answer
5.8 × 10⁵ m/s
Step 1: Heisenberg's uncertainty principle: Δx · Δv ≥ h/(4πm). Step 2: Minimum Δv = h/(4πm·Δx). Step 3: Δv = (6.626 × 10⁻³⁴) / (4 × 3.14159 × 9.108 × 10⁻³¹ × 10⁻¹⁰). Step 4: Denominator = 4 × 3.14159 × 9.108 × 10⁻⁴¹ = 12.566 × 9.108 × 10⁻⁴¹ = 1.145 × 10⁻³⁹. Step 5: Δv = 6.626 × 10⁻³⁴ / 1.145 × 10⁻³⁹ = 5.786 × 10⁵ ≈ 5.8 × 10⁵ m/s. Option B doubles the answer (error of not including 4π, just using π). Option C is a powers-of-10 error. Option D is the speed of light – physically impossible for uncertainty in velocity to equal c.
+85 more questions available
Practice AllFrequently Asked Questions
What are the important topics in Structure of Atom for ICSE Class 11 Chemistry?
How to score full marks in Structure of Atom — ICSE Class 11 Chemistry?
Sources & Official References
Content is aligned to the official syllabus. Refer to the board website for the latest curriculum.
More resources for Structure of Atom
Important Questions
Practice with board exam-style questions
Revision Notes
Key points for last-minute revision
Formula Sheet
All formulas in one place
Chapter Summary
Understand the chapter at a glance
Concept Maps
See how topics connect visually
Study Plan
Step-by-step plan to ace this chapter
Flashcards
Quick-fire cards for active recall
Syllabus
What topics to cover
NCERT Solutions
Every textbook question solved step by step
For serious students
Get the full Structure of Atom chapter — for free.
Quizzes, flashcards, AI doubt-solver and a step-by-step study plan for ICSE Class 11 Chemistry.