Renald A.
De Vera MAEd Science Education                                         03/09/2025
                                   SCNED 241
                 Creative Writing about the Atomic Theory Models
Output: Spoken word poetry/ Poem
Title: to be decided
Contents/Outline:
      I. Introduction
          A. Definition of an atomic model
          B. Importance of understanding atomic structure
          C. Overview of the progression of atomic models
    II.   Early Philosophical Theories of the Atom
          A. Democritus’ Atomic Theory (5th Century BCE)
                 1. Proposed that all matter is made of tiny, indivisible particles called
             atomos.
                 2. Atoms differ in size, shape, and motion but cannot be created or
             destroyed.
               3. No experimental evidence; purely philosophical.
          B. Aristotle’s Four Elements Theory (4th Century BCE)
               1. Rejected Democritus' atomic theory.
                2. Proposed that all matter is composed of four elements such as earth,
             water, air, and fire.
               3. His view was widely accepted for over a thousand years, delaying atomic
             theory development.
   III.   Scientific Development of Atomic Models
          A. John Dalton’s Atomic Theory (1803)
               1. First scientific atomic model based on experiments.
               2. Dalton’s Postulates:
                          - Matter is made of indivisible atoms.
                          - Atoms of the same element are identical.
                          - Atoms combine in whole-number ratios to form compounds.
                          - Chemical reactions involve rearranging atoms but do not create or
                     destroy them.
               3. Limitations: Did not explain subatomic particles.
   IV.    Discovery of Subatomic Particles
          A. Eugen Goldstein’s Discovery of Canal Rays (1886) – Evidence of Protons
            1. Canal Ray Experiment
                 - Observed positively charged rays traveling in the opposite direction of
          cathode rays.
               - Later identified as protons
          .
       B. J.J. Thomson’s Discovery of the Electron (1897) – Plum Pudding Model
            1. Cathode Ray Tube Experiment
                    - Discovered negatively charged particles (electrons).
            2. Proposed the Plum Pudding Model
                     - Atom consists of a positively charged pudding with embedded
          electrons like plums.
            3. Limitations: Could not explain the presence of a nucleus.
 V.    Discovery of the Atomic Nucleus
       A. Ernest Rutherford’s Gold Foil Experiment (1911) – Nuclear Model/Planetary
          Model
           1. Experiment:
                    - Fired alpha particles at thin gold foil.
                    - Most passed through, but some were deflected at sharp angles.
           2. Conclusion
                    - Atoms have a dense, positively charged nucleus.
                    - Electrons move outside the nucleus.
           3. Limitations: Did not explain electron arrangement or atomic stability.
VI.    Refining the Atomic Model: Electrons and Energy Levels
       A. Niels Bohr’s Planetary Model (1913)
           1. Proposed that electrons orbit the nucleus in fixed energy levels.
           2. Electrons absorb/emit energy when jumping between levels
VII.   The Quantum Mechanical Model of the Atom
       A. Louis de Broglie’s Wave-Particle Duality (1924)
           1. Suggested that electrons behave as both particles and waves.
           2. Introduced the concept of matter waves.
       B. Erwin Schrödinger’s Electron Cloud Model (1926)
              1. Developed the Schrödinger Equation, describing electron behavior
          mathematically.
             2. Proposed that electrons exist in probability clouds (orbitals), not fixed
          orbits.
               3. Quantum Model Replaced Bohr’s Model by incorporating wave
          mechanics.
          C. Werner Heisenberg’s Uncertainty Principle (1927)
               1. Stated that it is impossible to know both the position and momentum of an
             electron simultaneously.
               2. Reinforced the idea of probability-based electron locations.
  VIII.    Discovery of the Neutron
A. James Chadwick’s Discovery of the Neutron (1932)
 1. Bombarded beryllium with alpha particles, producing a neutral radiation.
 2. Concluded that the radiation was made of uncharged particles neutrons.
 3. Importance: Explained atomic mass discrepancies and enabled nuclear fission research.