Which observation by Ernest Rutherford and his students refuted the plum pudding model?(1 point)
Responses
electron attraction
electron attraction
electron deflection
electron deflection
alpha particle attraction
alpha particle attraction
alpha particle deflection
alpha particle deflection
The correct observation that refuted the plum pudding model was the "alpha particle deflection".
The observation by Ernest Rutherford and his students that refuted the plum pudding model was the "alpha particle deflection."
To understand how they made this observation, we need to first understand the plum pudding model. The plum pudding model was a theory proposed by J.J. Thomson that suggested atoms were made up of a positively charged "pudding" with negatively charged electrons dispersed throughout, much like plums in a pudding.
To test this model, Ernest Rutherford and his students conducted an experiment known as the "gold foil experiment." In this experiment, they directed a stream of alpha particles (positively charged particles) at a thin sheet of gold foil.
According to the plum pudding model, the positively charged pudding should have repelled the positively charged alpha particles and caused them to scatter in all directions. However, what they observed was quite different.
Most of the alpha particles passed through the gold foil without any deflection, which supported the idea that most of the atom is empty space. However, a small fraction of the alpha particles were deflected at large angles, and a few were even reflected straight back.
This observation of significant deflections and reflections of alpha particles led Rutherford to conclude that the plum pudding model was incorrect. Instead, he proposed a new model where the majority of the atom's mass and positive charge were concentrated in a tiny, dense region called the nucleus, and the electrons orbited around it.
Therefore, the alpha particle deflection observation by Rutherford and his students refuted the plum pudding model.