Which statement best describes Ernest Rutherford's gold foil experiment?

• A. Electrons were scattered off a gold foil to determine their mass.
• B. Alpha particles were directed at a thin sheet of gold foil, and most passed through, but some were deflected at large angles.
• C. Gold atoms were bombarded with neutrons to observe nuclear fission.
• D. Hydrogen gas was ionized to study the emission spectrum.

Answer: (B)

Verified step by step guidance

1. Understand the historical context: Ernest Rutherford's gold foil experiment was designed to probe the structure of the atom by observing how particles interact with a thin metal foil.
2. Identify the particles used: Rutherford used alpha particles, which are positively charged helium nuclei, to bombard the thin gold foil.
3. Observe the results: Most alpha particles passed straight through the foil, indicating that atoms are mostly empty space, but some were deflected at large angles, suggesting a small, dense, positively charged nucleus.
4. Interpret the significance: The deflection of some alpha particles led to the conclusion that the atom has a tiny, dense nucleus at its center, disproving the earlier plum pudding model.
5. Summarize the key point: The experiment showed that alpha particles were directed at a thin sheet of gold foil, and while most passed through, some were deflected at large angles, revealing the nuclear structure of the atom.