Draw Bohr’s Model for the following atoms, indicating the locations of electrons, protons, and neutrons:

• Protons: 19

• Neutrons: 39 – 19 = 20

• Electrons: 19

• The Bohr model would show 19 electrons arranged in 4 shells:

  • K shell (1s): 2 electrons

  • L shell (2s, 2p): 8 electrons

  • M shell (3s, 3p): 8 electrons

  • N shell (4s): 1 electron

(b) Silicon (Atomic No. 14, Mass No. 28)

• Protons: 14

• Neutrons: 28 – 14 = 14

• Electrons: 14

• The Bohr model would show 14 electrons arranged in 3 shells:

  • K shell (1s): 2 electrons

  • L shell (2s, 2p): 8 electrons

  • M shell (3s): 4 electrons

(c) Argon (Atomic No. 18, Mass No. 39)

• Protons: 18

• Neutrons: 39 – 18 = 21

• Electrons: 18

• The Bohr model would show 18 electrons arranged in 3 shells:

  • K shell (1s): 2 electrons

  • L shell (2s, 2p): 8 electrons

  • M shell (3s, 3p): 8 electrons