Which statement best summarizes the importance of Ernest Rutherford's gold foil experiment?

• A. It showed that atoms are indivisible and cannot be broken down further.
• B. It proved that electrons are arranged in fixed orbits around the nucleus.
• C. It confirmed that protons and neutrons are evenly distributed throughout the atom.
• D. It demonstrated that atoms have a small, dense, positively charged nucleus.

Answer: (D)

Verified step by step guidance

1. Recall the context of Rutherford's gold foil experiment: alpha particles were directed at a thin sheet of gold foil to observe their scattering patterns.
2. Understand the expected outcome based on the plum pudding model, which predicted that alpha particles would pass through with minimal deflection because positive charge was thought to be spread out evenly.
3. Analyze the actual observations: most alpha particles passed through, but some were deflected at large angles, and a few even bounced back.
4. Interpret these results to conclude that the atom must have a small, dense, positively charged center (nucleus) that repels the positively charged alpha particles, causing the deflections.
5. Recognize that this experiment disproved the plum pudding model and led to the nuclear model of the atom, highlighting the nucleus's existence and its properties.