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Revision Notes

Structure of Atom — Revision Notes

ICSE · Class 11 · Chemistry

Structure of Atom revision notes for ICSE Class 11 Chemistry: 4 topics in quick points. Part of the ICSE Class 11 Chemistry syllabus.

89 questions56 flashcards8 formulas & key relations5 concepts

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Key Topics to Revise

1

1. Fundamental Particles and Early Atomic Ideas

  • Matter is made of extremely small atoms.
  • Atoms of the same element are alike and differ from atoms of other elements.
  • The three fundamental subatomic particles are electron, proton, and neutron.
2

2. Atomic Number, Mass Number, Isotopes and Isobars

  • Atomic number is the number of unit positive charges on the nucleus.
  • For a neutral atom, atomic number equals number of protons and electrons.
  • Mass number is the sum of protons and neutrons in the nucleus.
3

3. Nature of Light and Electromagnetic Radiation

  • Wave theory explains reflection, refraction, interference and diffraction.
  • Wave theory cannot explain black body radiation and photoelectric effect.
  • Planck proposed that radiant energy is emitted or absorbed as quanta or photons.
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4. Planck's Theory and Photoelectric Effect

  • Energy is emitted or absorbed in discrete packets.
  • Photoelectric effect is the emission of electrons from a metal surface when light falls on it.
  • Threshold frequency is the minimum frequency needed to eject electrons.

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Full Notes

Key Concepts

Matter was first viewed as beingAn electron is a negatively chargedA proton is a positively chargedA neutron is electrically neutralRutherford’s alpha

Frequently Asked Questions

What are the important topics in Structure of Atom for ICSE Class 11 Chemistry?
Key topics in Structure of Atom include Fundamental Particles and Early Atomic Ideas, Atomic Number, Mass Number, Isotopes and Isobars, Nature of Light and Electromagnetic Radiation, Planck's Theory and Photoelectric Effect. Study these first, then practise questions on each for Class 11 exams.
How should I revise Structure of Atom for Class 11 exams?
Learn the core ideas first, then work through the 89 practice questions on Structure of Atom. Revise definitions regularly and use flashcards for quick recall before the exam.

Sources & Official References

Content is aligned to the official syllabus. Refer to the board website for the latest curriculum.

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