Explain the concept of electron shells (or energy levels) and how electrons are distributed within them according to Bohr's model.
ChemistryClass 9CBSEAnswered 12 May 2026
Answer
Bohr's model proposes that electrons orbit the nucleus in specific, fixed energy levels called electron shells. Each shell can hold a maximum number of electrons: 2 in the first shell, 8 in the second, and 18 in the third (for the first few elements). Electrons fill the lowest energy shells first.
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