John Dalton (chemist)

John Dalton was a 19th-century chemist known for developing the atomic theory, which proposed that all matter is made up of tiny, indivisible particles called atoms. He suggested that each element has unique atoms, differing in weight, and that chemical reactions involve atoms rearranging but not changing individual atoms themselves. Dalton's work laid the foundation for modern chemistry, helping us understand the composition of substances and how they interact. His atomic model was a significant step toward explaining the nature of matter scientifically.