The atomic theory proposed by dalton has been

 The atomic theory proposed by John Dalton has been modified over time as new evidence and scientific knowledge have emerged. Dalton's original atomic theory, proposed in 1803, contained several key ideas:

1. Elements are composed of extremely small particles called atoms. 2. Atoms of a given element are identical in size, mass, and other properties; atoms of different elements differ in these respects. 3. Atoms cannot be subdivided, created, or destroyed. 4. Atoms of different elements combine in simple whole-number ratios to form chemical compounds. 5. In chemical reactions, atoms are combined, separated, or rearranged.

Some of these original postulates have since been revised:

- Atoms can be subdivided into smaller particles, such as protons, neutrons, and electrons. - Atoms of the same element can have different masses; these are known as isotopes. - Atoms are indeed divisible, as proven by nuclear reactions and particle physics experiments. - The modern understanding of atomic structure includes quantum mechanics, which explains the behavior of electrons in atoms.

Dalton's theory laid the groundwork for modern chemistry by providing a conceptual framework for understanding the composition of matter. However, as scientific methods and technology have advanced, the model has evolved substantially to incorporate new discoveries.