Rutherford’s alpha particle scattering experiment led to several key conclusions about the structure of the atom: most of the atom is empty space, the positive charge and mass of an atom are concentrated in a small, dense core called the nucleus, and electrons orbit the nucleus at a high speed.
Detailed Conclusions:
1. Most of the atom is empty space:
Most alpha particles passed straight through the gold foil, indicating that atoms are mostly empty.
2. Positive charge and mass concentrated in a nucleus:
A small number of alpha particles were deflected at large angles, and some were even deflected back, suggesting a dense, positively charged core within the atom, which Rutherford called the nucleus.
3. Electrons orbit the nucleus:
The experiment also suggested that the negatively charged electrons are located outside the nucleus, orbiting it.
4. The nucleus is much smaller than the atom:
The fact that only a small fraction of alpha particles were deflected by large angles indicates that the nucleus is very small compared to the size of the atom.