Which scientist is credited with developing the first scientific atomic theory?

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

Answer: (A)

Verified step by step guidance

1. Understand that the question is about the historical development of atomic theory in chemistry.
2. Recall that John Dalton is credited with formulating the first scientific atomic theory in the early 19th century, which proposed that matter is made up of indivisible atoms and that atoms of each element are identical in mass and properties.
3. Recognize that other scientists like J.J. Thomson, Ernest Rutherford, and Niels Bohr contributed later by discovering subatomic particles and refining the atomic model, but did not develop the first atomic theory.
4. Identify John Dalton as the correct answer because he laid the foundational principles of atomic theory that influenced modern chemistry.
5. Summarize that John Dalton's atomic theory was the first to provide a scientific explanation for the nature of atoms, distinguishing his work from the later contributions of the other scientists listed.