Question

question 4 of 10
how did ernest rutherford change the atomic model?
a. he showed that the atom could be divided into smaller particles.
b. he showed that the atom contained both positive and negative charges.
c. he showed that most of an atoms mass was located in the atoms nucleus.
d. he showed that electrons were located within an atoms nucleus.

Explanation:

• Option A: J.J. Thomson (discovered electrons) showed atoms could be divided into smaller particles (electrons), not Rutherford.
• Option B: J.J. Thomson's plum - pudding model (with electrons as negative charges and a 'soup' of positive charge) was the first to suggest atoms have both positive and negative charges.
• Option C: Rutherford's gold - foil experiment led to the nuclear model. In this experiment, most alpha particles passed through the gold foil, but a small number were deflected at large angles. This suggested that most of the atom's mass and positive charge (nucleus) was concentrated in a small region (the nucleus), and the rest of the atom was mostly empty space.
• Option D: Electrons are outside the nucleus. Rutherford's model had electrons orbiting the nucleus (similar to planets around the sun), not inside the nucleus.

Answer:

C. He showed that most of an atom's mass was located in the atom's nucleus.