Ernest Rutherford: The Geiger-Marsden Experiment

Ernest Rutherford is the man behind the discovery of the central charge in a nucleus. This significant finding changed scientists view on atoms The discovery of the nucleus is one of, if not the most important to have ever been made. In this essay I will be discussing how previous assumptions of the atom's shape, curiosity and an accident led to Rutherford's discovery of the proton. Data and equations from his original journal will also be discussed to further prove the presence of a central charge.
Before the discovery of the nucleus, scientists accepted The Plum Pudding Model proposed by J. J Thomson. In this theory of the atom it was thought to have negative charged electrons surrounded by positively charged matter. Both the positive matter and negative electrons were in equal amounts leading to a neutral atom. It was named the Plum Pudding Model because it was visualised as a pudding, where the raisin symbolised the electrons and the pudding represented positive matter.
Ernest
Rutherford did not conduct the experiment but supervised and explained the observations, it was done by Hans Geiger and Ernest Marsden. The gold foil experiment consisted of an apparatus that emitted alpha particles which we now know to be helium nuclei, a gold foil which was 0.00004cm thick and a detector which was a zinc sulphide screen that detected that alpha particles once it passed the gold foil. Alpha particles were used because they were positively charged, extremely dense and travelled at a high speed. To count the particles Geiger and Marsden would sit in the dark for thirty minutes to an hour so their eyes would adjust. Then they would count the alpha particles that were hitting the zinc sulphide screen using a microscope. They would switch turns every thirty minutes so they could be as precise and accurate as