Rutherford's a-particle scattering experiment on gold foil is responsible for the discovery of:

The correct answer is Atomic nucleus.

Key Points

• The discovery of the atomic nucleus was a result of Rutherford's famous alpha-particle scattering experiment conducted in 1911.
• Rutherford observed that a small fraction of alpha particles were deflected at large angles, while most passed through the gold foil, indicating the presence of a dense, positively charged core.
• This dense core was named the nucleus, which contains most of the atom's mass and is positively charged due to the presence of protons.
• The experiment disproved the earlier "plum pudding model" proposed by J.J. Thomson, leading to the development of the nuclear model of the atom.
• This groundbreaking discovery laid the foundation for modern atomic theory and nuclear physics.

Additional Information

• Alpha particles:
  • Alpha particles are helium nuclei consisting of two protons and two neutrons.
  • In Rutherford's experiment, alpha particles were used as projectiles to study atomic structure.
• Gold foil experiment:
  • In this experiment, a thin sheet of gold foil was bombarded with alpha particles.
  • Most particles passed through the foil undeflected, while some were scattered at large angles, leading to the conclusion of a dense nucleus.
• Nuclear model of the atom:
  • Rutherford proposed that an atom consists of a small, dense nucleus surrounded by electrons in empty space.
  • This model replaced the "plum pudding model" and introduced the concept of a central nucleus.
• Limitations of Rutherford's model:
  • While the nuclear model explained the presence of the nucleus, it could not explain the stability of electrons in orbit.
  • This limitation was later addressed by Niels Bohr in his atomic model.
• Impact on modern science:
  • The discovery of the nucleus was pivotal in advancing fields like nuclear physics, quantum mechanics, and chemistry.
  • It also led to the discovery of protons and neutrons as subatomic particles within the nucleus.