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Atomic Structure

220 original questions for NEET, JEE Main and JEE Advanced, written for this chapter's 7 topics and solved independently a second time before publication. Physical chemistry here means numerical problem solving: data chosen so the arithmetic is clean, and every value computed before the question was written.

220questions
44NEET level
88JEE Main
88JEE Advanced
7topics
Practice this chapter Learn mode with solutions All 220 questions with solutions

Sample questions

5 of the 220 questions in this chapter. Answers and solutions open below each one.

Question 1 of 5, NEET levelSubatomic particles, atomic models, nucleus
In the gold foil experiment, a very small fraction of the alpha particles bounced back through large angles. Which conclusion was drawn mainly from this observation?
  1. AElectrons are embedded uniformly in a sphere of positive charge
  2. BPositive charge and most of the mass of the atom are concentrated in a very small central region
  3. CElectrons move only in orbits of fixed energy
  4. DAlpha particles are heavier than the atoms of gold
Answer and solution
Answer: B. Large-angle reflection of a few heavy, positive alpha particles needs a strong repulsion from a tiny, massive, positively charged centre. A uniform positive sphere (Thomson model) cannot produce such deflections. Hence the nucleus concept.
Question 2 of 5, NEET levelQuantum theory of light and photoelectric effect
Among the following radiations, the photon of which has the highest energy?
  1. AInfrared
  2. BMicrowave
  3. CGreen light
  4. DUltraviolet
Answer and solution
Answer: D. Photon energy E = h nu is proportional to frequency. Of the four regions, ultraviolet has the highest frequency (shortest wavelength), so its photons carry the most energy.
Question 3 of 5, NEET levelBohr model: energy, radius, velocity, ionisation energy
The energy of the electron in the level of a hydrogen atom, taking , is
  1. A
  2. B
  3. C
  4. D
Answer and solution
Answer: C. For hydrogen . For : .
Question 4 of 5, NEET levelHydrogen spectrum and spectral series
The lines of the Lyman series in the hydrogen spectrum lie in the
  1. Aultraviolet region
  2. Bvisible region
  3. Cinfrared region
  4. Dmicrowave region
Answer and solution
Answer: A. Lyman lines arise from transitions to , the largest energy gaps in hydrogen (10.2 eV to 13.6 eV), so their wavelengths (about 91 nm to 122 nm) are in the ultraviolet.
Question 5 of 5, NEET levelde Broglie wavelength and uncertainty principle
If the speed of a moving electron is doubled while its mass stays the same, its de Broglie wavelength
  1. Aremains unchanged
  2. Bbecomes double
  3. Cbecomes half
  4. Dbecomes one-fourth
Answer and solution
Answer: C. Since , the wavelength is inversely proportional to speed. Doubling halves .

How to use this chapter

Start with a 10-question set in learn mode: each answer is checked at once and the solution opens. When your accuracy in a topic is above 80%, switch to test mode, which uses the real NEET and JEE marking (+4 for a correct answer, -1 for a wrong one, partial marking on multiple-correct JEE Advanced items) and a timer of 80 seconds per question. Your chapter-wise accuracy is saved in your browser and shown on the progress page.