Why was Niels Bohr's atomic model considered superior to earlier atomic models?

• A. It explained the stability of atoms and the discrete spectral lines of hydrogen by introducing quantized electron orbits.
• B. It suggested that atoms are indivisible and cannot be broken down into smaller particles.
• C. It described electrons as waves spread throughout the atom without specific orbits.
• D. It proposed that electrons are embedded in a positively charged sphere, like plums in a pudding.

Answer: (A)

Verified step by step guidance

1. Step 1: Understand the context of atomic models before Bohr. Early models, such as Dalton's and Thomson's, had limitations in explaining atomic stability and spectral lines.
2. Step 2: Recognize that Bohr introduced the concept of quantized electron orbits, meaning electrons can only occupy certain allowed energy levels without radiating energy continuously.
3. Step 3: Note that this quantization explained why atoms are stable—electrons do not spiral into the nucleus because they remain in fixed orbits with specific energies.
4. Step 4: Understand that Bohr's model also explained the discrete spectral lines of hydrogen by associating them with electrons jumping between these quantized orbits, emitting or absorbing photons of specific energies.
5. Step 5: Compare Bohr's model to other options: it is superior because it explains both atomic stability and spectral lines, unlike models that treat atoms as indivisible, electrons as waves without orbits, or electrons embedded in a positive sphere.