Question

Which part of John Dalton's theory was disproved by J.J. Thomson's cathode-ray tube experiments?
A. Atoms are indivisible
B. Atoms can join together
C. Atoms are small
D. Atoms can form new substances

Answers

GPT-4o mini
The part of John Dalton's theory that was disproved by J.J. Thomson's cathode-ray tube experiments is:

**A. Atoms are indivisible.**

Thomson's experiments showed that atoms could be divided into smaller particles, specifically electrons, which indicated that atoms were not indivisible as Dalton had proposed.