The first atomic model that showed the internal structure of an atom was developed by J.J. Thomson in 1904. Thomson discovered the electron in 1897 and proposed the "plum pudding model," which depicted the atom as a sphere of positive charge with negatively charged electrons embedded within it. This was the first model to describe an internal structure of the atom rather than treating it as indivisible
. However, the first detailed model to show the atom's internal structure with a dense nucleus at its center was developed by Ernest Rutherford in 1911. Rutherford's gold foil experiments revealed that atoms have a tiny, dense, positively charged nucleus containing most of the atom's mass, surrounded by electrons orbiting at a distance. This nuclear model replaced Thomson's plum pudding model and was the first to accurately describe the atom's internal structure based on experimental evidence
. In summary:
- J.J. Thomson developed the first atomic model showing internal structure (plum pudding model) in 1904.
- Ernest Rutherford developed the first model showing a nucleus at the center of the atom in 1911, revealing the true internal structure of the atom.
Rutherford's model is considered the first to show the actual structure inside an atom with a nucleus and electrons
