Question

According to J J Thomson model, Electrons in atom are
(A) revolving around nucleus
(B) embedded in nucleus
(C) static around nucleus
(D) none of these

Answer 1

The concept of nucleus was introduced by Rutherford in the year 1911. J J Thomson’s model of the atom proposed in the year 1904 is known as plum pudding model.

Complete step by step answer:
-As we know that the concept of electron was discovered by J J Thomson in the year 1897. Through his study, he had introduced a model known as plum pudding model. He had proposed the theory that the atom is made up of tiny particles called corpuscles. These negatively charged particles were surrounded by a soup of positively charged particles. Thus the negative charges were neutralized by the positive charged soup. Here, he had applied the fact that positive charge gets neutralized with negative charge.
-He had related the whole structure with plums being surrounded by the pudding, just like in a pudding. Here the electrons or the corpuscles act as the plums and the positively charged soup as the pudding. It is from this concept that the atom model by J J Thomson got the name “plum pudding model”. The corpuscles were supposed to be present inside the atom as rings that rotate.
-As we can see, at this time, the concept of nucleus wasn’t yet developed. It was in 1911 that the scientist Rutherford proposed the idea of nucleus. So the theory by J J Thomson cannot be related to the nucleus.So according to J J Thomson, electrons in the atom were not connected with the nucleus.
Therefore the correct option is option (d).

Note: The word electron was proposed by G J Stoney in 1894. In 1909 the plum pudding model by J J Thomson was proved to be wrong by the gold foil experiment conducted by Hans Geiger and Ernst Marsden.