Question

what important contribution was made by rutherfords atomic - structure model? the identification of neutrons the identification of alpha particles the identification of distinct electron orbitals the identification of a dense, positive nucleus

Explanation:

Rutherford's atomic - structure model was based on his gold - foil experiment. He discovered that most of the atom is empty space with a small, dense, positively - charged nucleus at the center. This was a significant departure from previous models. The identification of a dense, positive nucleus was his important contribution. Alpha particles were used in his experiment, but their identification was not the main contribution of his atomic model. Neutrons were discovered later by Chadwick. Distinct electron orbitals were part of later quantum - mechanical models.

Answer:

the identification of a dense, positive nucleus