Which statement is NOT part of Dalton's atomic theory?

• A. Atoms can be divided into protons, neutrons, and electrons.
• B. Atoms of different elements combine in simple whole-number ratios to form compounds.
• C. Chemical reactions involve the rearrangement of atoms.
• D. Atoms of the same element are identical in mass and properties.

Answer: (A)

Verified step by step guidance

1. Review Dalton's atomic theory, which includes the following key points: (1) Atoms are indivisible particles; (2) Atoms of the same element are identical in mass and properties; (3) Atoms of different elements combine in simple whole-number ratios to form compounds; (4) Chemical reactions involve the rearrangement of atoms, but atoms themselves are not created or destroyed.
2. Identify the statement that contradicts Dalton's theory. Dalton proposed that atoms are indivisible, meaning they cannot be broken down into smaller particles.
3. Recognize that the statement 'Atoms can be divided into protons, neutrons, and electrons' contradicts Dalton's theory because it refers to subatomic particles, which were discovered after Dalton's time.
4. Confirm that the other statements align with Dalton's theory: atoms of the same element are identical, atoms combine in whole-number ratios, and chemical reactions rearrange atoms.
5. Conclude that the statement about atoms being divisible into protons, neutrons, and electrons is NOT part of Dalton's atomic theory.