Chapter 4, Problem 109A

Interpretation Introduction

Interpretation:

The other experiment which dispute of J. J. Thomson’s plum pudding atomic model needs to be explained.

Concept introduction:

In Thomson's plum pudding model, in an atom the electrons are present in a positive charge sphere like seeds in a watermelon. The positive matter was thought to be pulp or a softy material. The total positive charge inside the atom is equal to the total negative charge carried by the electron, this makes the atom electrically neutral.

Plum pudding model

Explanation of Solution

The Rutherford modified the atomic model of Sir J. J. Thomson. According to the accepted atomic model, in which an atomic mass and the atomic charge are equally spread throughout the atom. But in the Rutherford experiment, the result is different from the previous atomic model.

The Rutherford’s experiment of thin gold foil has different results from the plum pudding model.

The step up is represented as follows:

Rutherford model

Conclusion

It was Rutherford's thin gold foil experiment. The result contradicts the plum pudding atomic model.