Question

Chemists once believed that an atom was made of negative electrons dispersed inside a positive mass like raisins in pudding. An

experiment with radiation and gold foil demonstrated that most of an atom was made of empty space. After this experiment, they
adopted a new model of the atom that showed the electrons orbiting the nucleus of the atom from a distance. Which of the following
statements about the new model is true?
A. The new model is perfect and will not change.
B. The new model is a wrong model and will not last.
C. The new model fits the data worse than the old model.
D. The new model fits the data better than the old model.

Answer 1

Answer: D. The new model fits the data better than the old model.

Explanation: Rutherford's gold foil experiment (firing positively charged particles at a thin gold foil) found that most of the particles went right through the atom except at a small center we now call the nucleus. This determined that the center of the atom had a positive charge, thus the electrons must be outside of the center. Rutherford's discovery of the nucleus and proposed atomic structure was later refined by physicist Niels Bohr in 1913. The Bohr model is still used today.