Respuesta :
Explanation:
- Introduction: The Gold Foil Experiment of Rutherford proved the existence of a small but massive core for atoms, later became unique as an atom's nucleus. To observe the effect of alpha particles on matter Ernest Rutherford, Hans Geiger and Ernest Marsden performed their Gold Foil Experiment which rectified doubts regarding how the electrons are arranged within an atom.
- Experiment: Rutherford's Gold foil / Geiger–Marsden experiments performed by picking a gold foil because he wanted as thin layer as possible which was about 1000 atoms thick. As α-particles were doubly-charged helium ions, having mass of 4 u and fast-moving α-particles have a considerable amount of energy. It was expected that α-particles would be deflected by the sub-atomic particles in the gold atoms.
- Observation: The following observations were made: (i) Most of the fast moving α-particles passed straight through the gold foil. (ii) Some of the α-particles were deflected by the foil by small angles. (iii) Surprisingly one out of every 12000 particles appeared to rebound.
- Conclusion: Rutherford concluded from the α-particle scattering experiment that–(i) Most of the space inside the atom is empty because most of the α-particles passed through the gold foil without getting deflected. (ii) Very few particles were deflected from their path, indicating that the positive charge of the atom occupies very little space. (iii) A very small fraction of α-particles were deflected by 1800, indicating that all the positive charge and mass of the gold atom were concentrated in a very small volume within the atom. From the data he also calculated that the radius of the nucleus is about 105 times less than the radius of the atom.
- Further: On the basis of his experiment Rutherford put forward the nuclear model of an atom.
