Which scientist proposed the nuclear model of the atom after the gold foil experiment, discovering the atomic nucleus?

• A. Niels Bohr
• B. John Dalton
• C. Ernest Rutherford
• D. JJ Thomson

Answer: (C)

The main idea tested is how evidence from the gold foil experiment changed our picture of the atom. In this experiment, most alpha particles went straight through a thin gold foil, but a few were deflected at large angles. That pattern could only be explained if a tiny region of concentrated positive charge and most of the atom’s mass existed in a very small space—the nucleus. From this, the nuclear model of the atom was proposed: atoms are mostly empty space with a dense, positively charged nucleus containing protons, and electrons orbiting around it.

This was a departure from earlier ideas like Thomson’s plum pudding model, which pictured the positive charge spread out and electrons embedded within it. The gold foil results couldn’t be reconciled with that view, prompting the shift to the nuclear view. Niels Bohr later refined the model by introducing quantized electron orbits, but the fundamental nucleus idea comes from Rutherford’s work. John Dalton laid out the basic atomic theory long before these experiments, and JJ Thomson proposed the earlier plum pudding concept. So the scientist who proposed the nuclear model after the gold foil experiment and discovered the atomic nucleus is Ernest Rutherford.