Rutherford’s Model
An experiment that radically changed our view of the atom
- Bombarding materials with alpha particles (He++) (determining the shape of an object…)
- The target was a thin gold plate
- expected that the deflection of the alpha particles is small, since electrons have 7300 times smaller mass, and the positive charge is uniformly distributed
Surprise! A small number of alpha particles were scattered in backward direction (like hitting a wall….)
To explain the experimental results Rutherford proposed a new model (the solar system model of the atoms)
- positive charge located in a very tinny place: the nucleus
- electrons orbit the nucleus like Planets the Sun
The model have the same problems as the one proposed by Thomson!
+ electrons in circular motion should constantly radiate
electromagnetic waves and should quickly loose its energy!