Thomson and Rutherford's experiments

AI Thread Summary
Thomson's "plum pudding" model suggested that atoms were composed of positive and negative charges evenly distributed, which would imply that alpha particles should pass through gold foil without deflection. However, Rutherford's Gold Foil Experiment revealed that alpha particles experienced significant deflections, indicating the presence of a concentrated nucleus. The discussion highlights that the large deflections observed were due to the concentrated mass of positive nuclei, contradicting Thomson's model. The realization that the nucleus is not evenly distributed but rather a small, dense center explains the unexpected results of the experiment. Ultimately, Rutherford's findings led to the modern understanding of atomic structure, disproving the plum pudding model.
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Homework Statement


If Thomson's "plum pudding" model was correct, what could have happened when Rutherford fired high energy alpha particles at gold foil?Select all that are True.
Alpha particles are reflected.
Alpha particles pass right through with no deflection.
Alpha particles experience small deflections.
Alpha particles experience large deflections.
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The Attempt at a Solution



I understand Thomson had discovered that atoms are composite objects, made of pieces with positive and negative charge, and that the negatively charged electrons within the atom were very small compared to the entire atom. Also, how Rutherford's Gold Foil Experiment proved the existence of a small massive center to atoms, which would later be known as the nucleus of an atom.

Wouldn't this mean Alpha particles would pass right through with no deflection since a nucleus hasn't been established yet?
 
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I believe the right answer is
Alpha particles pass right through with no deflection.
 
That is what I tried and it was wrong :(
 
The positive nuclei have the largest mass and would then be evenly distributed throughout the "pudding".
How would such a distribution influence the deflection?
The large deflection observed in the real experiment came about as a result of the nuclei being bound together in one large concentrated mass.
 
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