The Rutherford nuclear model of atom predicts that atoms are unstable because the accelerated electrons revolving around the nucleus must be ______ in the nucleus. 

The correct answer is spiral.

Key Points

• The Rutherford nuclear model predicts that electrons revolve around the nucleus in orbits due to electrostatic forces.
• According to classical electromagnetic theory, an accelerating electron would emit radiation, losing energy in the process.
• This energy loss would cause the electron to spiral inwards towards the nucleus.
• As the electron spirals inwards, it would eventually collide with the nucleus, leading to the instability of the atom.
• This instability, predicted by the Rutherford model, contradicts the observed stability of atoms.

Additional Information

• Rutherford's Nuclear Model
  • Proposed by Ernest Rutherford in 1911 based on the gold foil experiment.
  • Suggested that most of the atom's mass is concentrated in a small, positively charged nucleus.
  • Electrons revolve around this nucleus similar to planets orbiting the sun.
• Classical Electromagnetic Theory
  • States that any charged particle undergoing acceleration emits electromagnetic radiation.
  • This emission of radiation causes the particle to lose energy.
• Niels Bohr's Model
  • Proposed in 1913 to address the limitations of Rutherford's model.
  • Introduced the concept of quantized electron orbits where electrons do not radiate energy while in these stable orbits.
• Quantum Mechanics
  • Further developed the understanding of atomic structure and electron behavior.
  • Explains the stability of atoms through principles such as wave-particle duality and the uncertainty principle.