Answer: Nucleus.
- A Electrons
- B Outer shell
- C Nucleus
- D Vacuum around atom
Correct answer: C. Nucleus
Explanation: Protons and neutrons are much heavier than electrons, and both are in the nucleus.
Bohr's model: electrons occupy fixed circular shells (K, L, M) around the nucleus, with each shell holding up to 2n2 electrons.
Concept context
Explore how electrons are arranged inside an atom. Covers Bohr's model, quantum numbers, Heisenberg's uncertainty principle, shapes of s, p, d orbitals, and electronic configuration rules.