Which statement correctly compares the modern quantum model of the atom to John Dalton's model?

• A. The modern quantum model describes electrons as existing in probability clouds, while Dalton's model considered atoms as indivisible solid spheres.
• B. Dalton's model includes the concept of electron energy levels, while the quantum model does not.
• C. The quantum model and Dalton's model both state that atoms are the smallest particles and cannot be divided further.
• D. Both models describe atoms as having a dense nucleus surrounded by electrons in fixed orbits.

Answer: (A)

Verified step by step guidance

1. Step 1: Understand John Dalton's atomic model. Dalton proposed that atoms are indivisible, solid spheres that make up matter. His model did not include any internal structure such as electrons or a nucleus.
2. Step 2: Understand the modern quantum model of the atom. This model describes electrons not as particles in fixed orbits, but as existing in regions of space called probability clouds or orbitals, where there is a certain likelihood of finding an electron.
3. Step 3: Compare the two models based on their descriptions of atomic structure. Dalton's model treats atoms as solid, indivisible spheres without internal components, while the quantum model includes a nucleus and electrons distributed in probabilistic clouds.
4. Step 4: Evaluate the incorrect statements: Dalton's model does not include electron energy levels, so any statement claiming it does is false. Also, Dalton's model does not describe a nucleus or fixed electron orbits, so statements suggesting these are common to both models are incorrect.
5. Step 5: Conclude that the correct comparison is that the modern quantum model describes electrons as existing in probability clouds, whereas Dalton's model considered atoms as indivisible solid spheres.