SAMPLE Chemistry

1897 J.J Thomson’s Plum Pudding Model: Joseph John Thomson, a prominent physicist, proposed the existence of electrons within a positively charged ‘pudding-like’ substance. He challenged the idea of indivisible atoms and introduced the concept of the plum pudding model.

1912 Ernest Rutherford’s Nuclear Model: Rutherford’s groundbreaking nuclear model, derived from his gold foil experiment, revealed that atoms consist of a tiny, positively charged nucleus at the center, containing most of the mass. Electrons were found to orbit around the nucleus, akin to planets around the sun, dispelling the previous notion of a uniformly distributed positive charge throughout the atom. This model laid the foundation for a more nuanced understanding of atomic structure. 1913 Niels Bohr’s planetary Model: Bohr’s atomic model, a refinement of earlier models, suggested that electrons orbit the nucleus in fixed energy levels or shells. Electrons can jump between these levels by absorbing or emitting discrete amounts of energy, leading to the observation of distinct spectral lines. This idea provided a more precise explanation for the behavior of electrons within the atom and marked a significant advancement in our understanding of atomic structure.

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