Question

scientists have changed the model of the atom as they have gathered new evidence. one of the atomic models is shown below. what experimental evidence led to the development of this atomic model from the one before it? a few of the positive particles aimed at a gold foil seemed to bounce back. the colors of light emitted from heated atoms had very specific energies. experiments with water vapor showed that elements combine in specific proportions. cathode rays were bent in the same way whenever a magnet was brought near them.

Explanation:

The atomic model shown is Rutherford's nuclear model, which replaced Thomson's "plum pudding" model. The key experimental evidence that led to this model was Rutherford's gold foil experiment, where a small fraction of positively charged alpha particles bounced back when fired at a thin gold foil, proving the existence of a dense, positively charged atomic nucleus.

Answer:

A. A few of the positive particles aimed at a gold foil seemed to bounce back.