we can know where the element is .
Pennsylvania
The Bohr Model, and its the basis of quantum theory
he did not develop anything regarding the 'atomic theory' for he was against that theory.
Niels Bohr is considered the founder of the modern atomic model.
The Electron Cloud model
No, the atomic theory is not always the model of matter. While the atomic theory is widely used and supported, there are other models, such as the quantum mechanical model, that provide a more detailed understanding of matter at the atomic and subatomic levels. These models build upon the atomic theory but also incorporate additional concepts from quantum mechanics.
Dalton's theory was irrelevant to the total compensation of of the Atomic Mass.
Electron Cloud Model.
He started working on the atomic theory in 1892. He developed the Saturnian Model in 1904.
The most accurate, but not user friendly and usable model is the quantum mechanic atom model (QM model)
Excepting philosophical atomism John Dalton is the first to elaborate an atomic theory.
Thomson Atomic Model