Oppositely charged objects attract each other. This attraction holds electrons in atoms and holds atoms to one another in many compounds. However, Ernest Rutherford’s model of the atom failed to explain why electrons were not pulled into the atomic nucleus by this attraction. What change to the atomic model helped solve the problem seen in Rutherford’s model?
Answer
A
Thomson’s work with atomic spectra led him to say that the electrons were limited to existing in certain energy levels, like standing on the rungs of a ladder.
B
Bohr’s work with atomic spectra led him to say that the electrons were limited to existing in certain energy levels, like standing on the rungs of a ladder.
C
Thomson’s work with cathode rays led him to say that the electrons were located within the mass of positive material, like plums in a pudding.
D
Bohr’s work with cathode rays led him to say that the electrons were located within the mass of positive material, like plums in a pudding.
Explanation
Rutherford’s model did not explain why negatively charged electrons would remain outside the positively charged nucleus instead of being pulled into it. Bohr proposed that electrons can occupy only certain energy levels, like rungs on a ladder, rather than any distance from the nucleus. This model helped explain the atom’s stability, so the correct choice is “Bohr’s work with atomic spectra…”
AI-written and checked against the verified answer.