Chapter 28, Problem 1RQ

To determine

The reason that the electrons in the Rutherford model fall into the nucleus.

Answer to Problem 1RQ

Solution:

The reason for electrons to fall into the nucleus, according to the Rutherford atomic model, is the force of attraction between the positive nucleus and the negatively-charged electron.

Explanation of Solution

Introduction:

The Rutherford atomic model is also known as the planetary or nuclear model of an atom. This model designated the atom as a positively charged, dense, tiny core called as a nucleus. Electrons (negative constitutent of atom) constitute the mass of the atom. These electrons revolve at a certain distance from the nucleus similar to the way planets revolve around the Sun.

Explanation:

According to Rutherford’s postulate, electrons revolve at a very high speed around the nucleus of an atom in a particular orbit. However, accelerated charged particles release a certain amount of electromagnetic radiations. Therefore, the electrons revolving around the nucleus will also release electromagnetic radiation. This electromagnetic radiation will gain energy from the electronic motion, resulting in the shrinkage of the orbits. The orbits will shrink and collapse into the nucleus of the atom. The electrons will spiral into the nucleus in about ${10}^{-12}\text{ s}$.

The electron spirals inward towards the nucleus as shown in the diagram:

The given figure shows the emission of electromagnetic radiation by the accelerating electron as well as the shrinkage of the orbit of the electron.

Conclusion:

The force of attraction between the positive nucleus and the negatively-charged electron is the main cause for electrons to fall into the nucleus, according to the Rutherford atomic model.