Final answer:
John Dalton is the one who utilized experiments and scientific tools to study matter, significantly contributing to the atomic theory that serves as a foundation for modern chemistry.
Step-by-step explanation:
Among Democritus, John Dalton, and Aristotle, it was John Dalton who used experiments and scientific tools to study matter. In the 1800s, Dalton advanced our understanding of matter significantly with his atomic theory. Unlike the ancient Greek philosophers who pondered the nature of matter as a purely philosophical concept, Dalton supported his hypothesis with quantitative measurements and experiments. This practical approach to science led to his atomic theory being a cornerstone of modern chemistry. Dalton's dedication to teaching and science is exemplified by his early start as a teacher and his move to Manchester, where his scientific studies flourished and brought him much recognition.