Experience Chemistry Lesson 1.4-Modern Atomic Theory

Revising the Atomic Model

• 1926: Erwin Schrodinger

  • Proposed an equation that described the behavior of the electron in a hydrogen atom

    • Lead to discoveries about electrons in other atoms and the development of the Quantum Mechanical Model​

      • Similar to the Bohr model with electrons being limited to certain values

      • Different from Bohr model because electrons don't follow an exact path

Experience Chemistry | Lesson 1.4

Revising the Atomic Model

• Atomic Orbital: an area around the nucleus where there is a high probability of finding an electron

  • Boundaries are not clear and distinct, but fuzzy

Experience Chemistry | Lesson 1.4

The Shell Model

• The shell model of the atom is a simplified version of the quantum mechanical model

  • Described with four quantum numbers

    • Each shell has one or more sub-shells inside of it (l)

      • s, p, d, f

    • Each sub-shell holds at least one orbital that holds 2 electrons each

      • s= 1 orbital, 2 electrons

      • p=3 orbitals, 6 electrons

      • d= 5 orbitals, 10 electrons

      • f=7 orbitals, 14 electrons

Experience Chemistry | Lesson 1.4

Atomic Orbitals

• Shapes of orbitals

  • Shells have different shapes

  • Every shell has one s-orbital, which has a spherical shape

  • The probability of finding an electron does not depend on the direction the orbital is rotated

Experience Chemistry | Lesson 1.4

Atomic Orbitals

• Shapes of orbitals

  • Shells have different shapes

  • Every shell on the second energy level upwards has three p-orbitals

    • Dumb bell shaped, with 3 orbitals

      • Can face different directions

    • Electrons are found anywhere in the shape itself, but not outside of them

Experience Chemistry | Lesson 1.4

Atomic Orbitals

• Shapes of orbitals

  • Shells have different shapes

  • Ever shell from the third level up has a d-orbital

    • 5 orbitals holding 10 total electrons

Experience Chemistry | Lesson 1.4

Atomic Orbitals

• Shapes of orbitals

  • Shells have different shapes

  • Every shell from the fourth level up has a f-orbital

    • 7 orbitals holding 14 total electrons

    • Have a shape to complex to show as a picture

Experience Chemistry | Lesson 1.4

Atomic Orbitals

• Each orbital has different energy levels

  • s < p < d < f​

Experience Chemistry | Lesson 1.4