Who formulated atomic theory and the law of partial pressures?

Who formulated atomic theory and the law of partial pressures?

• A. John Dalton
• B. JJ Thomson
• C. Ernest Rutherford
• D. Niels Bohr

Answer: (A)

Dalton introduced the idea that matter is made of atoms and proposed that in a mixture of nonreacting gases, the total pressure is the sum of the partial pressures from each gas. This is Dalton's law of partial pressures, and together with his atomic theory, it established a lasting link between particle-level concepts and how gases behave. The other scientists made key advances in atomic structure—Thomson discovered the electron, Rutherford revealed the nucleus, and Bohr refined atomic models—but they did not formulate both the atomic theory and the law of partial pressures. So the scientist who did is John Dalton.

Dalton introduced the idea that matter is made of atoms and proposed that in a mixture of nonreacting gases, the total pressure is the sum of the partial pressures from each gas. This is Dalton's law of partial pressures, and together with his atomic theory, it established a lasting link between particle-level concepts and how gases behave. The other scientists made key advances in atomic structure—Thomson discovered the electron, Rutherford revealed the nucleus, and Bohr refined atomic models—but they did not formulate both the atomic theory and the law of partial pressures. So the scientist who did is John Dalton.