# How did Robert Millikan's oil drop experiment change the model of the atom?

Aug 22, 2014

It didn't.

J. J. Thomson discovered the electron in 1897. He calculated the charge-to-mass
($e$/$m$) ratio of the electron.

In 1904, he proposed the plum pudding model, in which the electrons were immersed in a positively charged "pudding".

In 1909, Millikan performed his famous oil drop experiment and determined the charge ($e$) of the electron.

The gold foil experiment was performed in 1909. It wasn't until 1911 that Rutherford wrote his paper proposing the nuclear model of the atom.

So Millikan's oil drop experiment didn't change the model of the atom.