Question

Which of the following is a drawback of the Rutherford model?
(A). The orbital revolution of the electron is not expected to be stable
(B). The electrons will follow a spiral path and then fall into the nucleus
(C). Both A and B
(D). None of the above

Answer 1

Hint: Rutherford’s model is based on the theory that the negatively charged electrons revolve around the positively charged nucleus in a circular path. The opposite charge will cause acceleration and as a result, it will cause the electrons to lose their energy.

Complete step-by-step solution -

The drawback of the Rutherford model is that the orbital revolution in a circular manner of the electron is unstable and as a result, the electron will follow a spiral path ultimately falling into the nucleus. So, option C is the correct one.
Let us first understand the origin and aspects of the Rutherford model then we will find out the drawbacks of the model.
- Rutherford carried out an experiment that is popularly known as the “Gold Foil Experiment” in which he took a source of alpha particles and allowed the beam of alpha particles to pass through a thin gold foil and observed the beam and postulated an atomic model.
- An alpha particle is a dipositive helium ion $({He}^{2+})$. On passing alpha particles through a thin gold foil, he observed that many of the particles passed straight through the foil. Few of the particles deflected from the path and very few of them rebounded completely. From all these observations he inferred the structure of the atom. Let us see the fundamental points of his atomic model:

• • Since most of the particles passed straight through the foil, he inferred that most of the spaces in the atom are empty.

• Few deflected from its original path and very few particles rebounded completely and that led him to conclude that there is a central positive charge that caused the deflection as the particles were also positively charged and we know that like charge repel each other.

• Finally, he concluded that the electrons revolve around the central positively charged mass in a circular mass.

We know that like charges repel and opposite charges attract each other. When a charged particle revolves in a circular manner around another oppositely charged particle it accelerates due to the attraction of opposite charges. Thus, in the Rutherford atomic model, the electrons will not be stable and it will get attracted towards the centre of the atom and it will follow a spiral path and fall into the nucleus. This was the major drawback of his model.

Note: The instability caused in the electron revolving among the nucleus is the reason for the electrons to follow a spiral path to the nucleus. So, both the given options are true. Don’t get confused.