Ernest Rutherford By Lauren Kintzley and Brynn Reese

● Born August 30, 1871 in Nelson, New Zealand ● Attended Canterbury College and graduated in 1893 with a double first in Mathematics and Physical Science. He continued to study here and received his Bachelors in Science, and later to be awarded with a scholarship to Trinity College. ● Researched under J. J. Thomson and and in 1897 was awarded a research degree. From there, Ruthford went to Montreal, Canada and took the post of MacDonald Chair of Physics at McGill University. ● In 1907,Ruthford returned to England to become a professor of physics at Manchester and in 1919 he succeeded Thomson’s position as Cavendish Professor of Physics at Cambridge ● Died on October 19, 1937 in Cambridge Biography

· Starting sometime around 1909, Rutherford began to notice that alpha particles would not always behave in accordance to the plum pudding model of an atom when fired at a piece of gold foil. These observations stimulated further research that was eventually published in 1911 and has been known ever since as Rutherford's Gold Foil Experiment. Most Important Work

Rutherford aimed a beam of alpha particles at a piece of gold foil that was 8.6 x 10^(-6) cm thick. In relation to the plum pudding model the alpha particles should pass right through the gold foil. Gold Foil Experiment

For the most part, during the experiment, the particles passed right through the gold foil (further backing up the "empty space" in the plum pudding model) · However a few of the particles deflected about 1 or 2 degrees · Even more shockingly 1 in 20,000 particles would deflect 90 degrees or more or even right back at the experimenter · His experiment shows that the atom has a tiny, massive nucleus. He can say its tiny because it only deflects some of the time, so it can’t be that large. Results

· He postulated the nuclear structure of an atom. Experiments showed that when alpha particles are fired into gas atoms, a few are violently deflected, which implies a dense, positively charged central region containing most of the atomic mass-- the nucleus! Part in Atomic Theory

The Rutherford model of the atom was simplified in a well known symbol showing electrons circling around the nucleus like planets orbiting the sun. This symbol became popular and has been used by various organizations around the world as a symbol for atoms and atomic energy in general. Part in Atomic Theory