Final answer:
Modern atomic theory was founded by John Dalton's postulates
Step-by-step explanation:
Modern atomic theory began with a series of postulates laid out by John Dalton almost 200 years ago. Dalton's revolutionary ideas were significantly based on experimental evidence such as the behavior of gases and the formulations of simple chemicals, advancing the understanding of matter from philosophical conjecture to scientific theory.
Dalton's atomic theory provided the foundation for modern chemistry by proposing that all substances are composed of indivisible atoms, which combine in fixed ratios to form compounds. This theory supported the law of definite proportions and was pivotal in moving away from the Aristotelian view of matter that had dominated for two millennia. While some aspects of Dalton's theory have been revised with subsequent discoveries, such as radioactivity and the divisibility of atoms into subatomic particles, the core principle that matter is made of atoms remains central to modern chemistry.