Chapter 4 of 5
Concept Maps
Structure of the Atom — Concept Maps
Punjab Board · Class 9 · Science
3 concept maps of Structure of the Atom for Punjab Board Class 9 Science, each also written out as a text outline.
45 questions36 flashcards4 formulas & key relations5 concepts
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3 Concept Maps
Structure of the Atom - Complete Overview
The map in words
- Structure of Atom
- Subatomic Particles
- Protons
- Positive charge
- In nucleus
- Electrons
- Negative charge
- In shells
- Neutrons
- No charge
- In nucleus
- Protons
- Atomic Models
- Thomson Model
- Pudding model
- Electrons in sphere
- Rutherford Model
- Nuclear model
- Mostly empty space
- Bohr Model
- Energy levels
- Discrete orbits
- Stable atoms
- Thomson Model
- Electron Configuration
- Energy Levels
- K shell n=1
- L shell n=2
- M shell n=3
- Bohr-Bury Scheme
- Max electrons 2n^2
- Fill inner first
- Max 8 in outer
- Energy Levels
- Key Properties
- Atomic Number
- Number of protons
- Defines element
- Mass Number
- Protons + neutrons
- Determines mass
- Valency
- Combining capacity
- Outermost electrons
- Atomic Number
- Special Cases
- Isotopes
- Same atomic number
- Different mass number
- Different neutrons
- Isobars
- Same mass number
- Different atomic number
- Different elements
- Isotopes
- Subatomic Particles
Structure of the Atom – Complete Chapter Overview
The map in words
- Structure of the Atom
- Sub-Atomic Particles
- Electron
- Discovered by Thomson
- Charge minus 1
- Negligible mass
- Proton
- Canal rays by Goldstein
- Charge plus 1
- Mass 1 u
- Neutron
- Discovered by Chadwick
- No charge
- Mass 1 u
- Electron
- Atomic Models
- Thomson Model
- Plum Pudding
- Electrons in positive sphere
- Explained neutrality
- Rutherford Model
- Gold Foil Experiment
- Nuclear Model
- Drawback - instability
- Bohr Model
- Fixed discrete orbits
- Shells K L M N
- Overcame Rutherford drawback
- Thomson Model
- Electron Distribution
- Formula 2n squared
- K shell max 2
- L shell max 8
- M shell max 18
- Outermost max 8
- Valency
- Valence electrons
- Octet rule
- Gain lose or share
- Atomic Number and Mass Number
- Atomic Number Z equals protons
- Mass Number A equals nucleons
- Neutrons equals A minus Z
- Isotopes and Isobars
- Isotopes same Z different A
- Isobars different Z same A
- Applications of isotopes
- Sub-Atomic Particles
Structure of the Atom - Concept Overview
The map in words
- Structure of Atom
- Sub-atomic Particles
- Electrons
- Negative charge
- Low mass
- In electron shells
- Protons
- Positive charge
- Found in nucleus
- Mass = 1u
- Neutrons
- No charge
- Found in nucleus
- Mass = 1u
- Electrons
- Atomic Models
- Thomson Model
- Pudding model
- Electrons embedded
- Rutherford Model
- Nuclear model
- Nucleus at center
- Electrons orbit
- Bohr Model
- Discrete orbits
- Energy levels
- Stable shells
- Thomson Model
- Electron Configuration
- K shell
- Max 2 electrons
- L shell
- Max 8 electrons
- M shell
- Max 18 electrons
- Valence electrons
- Outermost shell
- Determines valency
- K shell
- Atomic Properties
- Atomic Number
- Number of protons
- Element identity
- Mass Number
- Protons + Neutrons
- Total nucleons
- Isotopes
- Same element
- Different neutrons
- Isobars
- Different elements
- Same mass number
- Atomic Number
- Sub-atomic Particles
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Explore DiagramsFrequently Asked Questions
What are the important topics in Structure of the Atom for Punjab Board Class 9 Science?
Key topics in Structure of the Atom include Charged Particles in Matter – Discovery of Sub-Atomic Particles, Atomic Models – Thomson, Rutherford, and Bohr, Distribution of Electrons in Shells (Bohr-Bury Scheme), Valency. Study these first, then practise questions on each for Class 9 exams.
What do the concept maps for Structure of the Atom show?
The 3 maps show how the ideas in Structure of the Atom connect: Structure of the Atom - Complete Overview; Structure of the Atom – Complete Chapter Overview. Each map is also written out as an outline on this page.
How should I revise Structure of the Atom for Class 9 exams?
Learn the core ideas first, then work through the 45 practice questions on Structure of the 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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Formula Sheet
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Chapter Summary
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Flashcards
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Syllabus
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