Overview
This lecture explains how to draw a Bohr diagram for the element silicon, including understanding its structure and electron arrangement.
What is a Bohr Diagram?
- A Bohr diagram shows electrons around the nucleus of an atom using concentric rings.
- It is based on the Bohr model, which approximates electron arrangement and highlights the outermost shell (valence shell).
Steps to Draw a Bohr Diagram for Silicon
- Draw the nucleus at the center to represent protons and neutrons.
- Silicon has 14 protons, determined by its atomic number (14).
- Silicon also has 14 neutrons, found by rounding atomic weight and subtracting protons from the mass number.
- Electrons are drawn as dots on rings around the nucleus.
- The first ring holds a maximum of 2 electrons.
- The second ring can hold up to 8 electrons.
- The third ring holds any remaining electrons (for silicon, 4 electrons).
- Distribute electrons in pairs on each ring and space out electrons on the outer shell for symmetry.
Checking the Diagram
- Total number of electron dots should equal the atomic number (14 for silicon).
Key Terms & Definitions
- Bohr Diagram — a visual representation of an atom showing electrons on energy levels around the nucleus.
- Nucleus — the center of an atom, containing protons and neutrons.
- Atomic Number — the number of protons in an atom, uniquely identifying the element.
- Mass Number — the total number of protons and neutrons in the nucleus.
- Valence Shell — the outermost energy level of electrons in an atom.
Action Items / Next Steps
- Practice drawing Bohr diagrams for other elements.
- Review how to calculate neutrons using atomic and mass numbers.